4.6. C library API

4.6.1. <assert.h>

4.6.1.1. Assertion functions

Function	Description
assert	Place assertion.

4.6.1.1.1. assert

Description

Place assertion.

Definition

#define assert(e)    ...

Additional information

If NDEBUG is defined as a macro name at the point in the source file where <assert.h> is included, the assert() macro is defined as:

#define assert(ignore) ((void)0)    ...

If NDEBUG is not defined as a macro name at the point in the source file where <assert.h> is included, the assert() macro expands to a void expression that calls __SEGGER_RTL_X_assert().

When such an assert is executed and e is false, assert() calls the function __SEGGER_RTL_X_assert() with information about the particular call that failed: the text of the argument, the name of the source file, and the source line number. These are the stringized expression and the values of the preprocessing macros __FILE__ and __LINE__.

Notes

The assert() macro is redefined according to the current state of NDEBUG each time that <assert.h> is included.

4.6.2. <complex.h>

Nuclei C Runtime Library provides complex math library functions, including all of those required by ISO C99. These functions are implemented to balance performance with correctness. Because producing the correctly rounded result may be prohibitively expensive, these functions are designed to efficiently produce a close approximation to the correctly rounded result. In most cases, the result produced is within +/-1 ulp of the correctly rounded result, though there may be cases where there is greater inaccuracy.

4.6.2.1. Manipulation functions

Function	Description
cabs()	Compute magnitude, double complex.
cabsf()	Compute magnitude, float complex.
cabsl()	Compute magnitude, long double complex.
carg()	Compute phase, double complex.
cargf()	Compute phase, float complex.
cargl()	Compute phase, long double complex.
cimag()	Imaginary part, double complex.
cimagf()	Imaginary part, float complex.
cimagl()	Imaginary part, long double complex.
creal()	Real part, double complex.
crealf()	Real part, float complex.
creall()	Real part, long double complex.
cproj()	Project, double complex.
cprojf()	Project, float complex.
cprojl()	Project, long double complex.
conj()	Conjugate, double complex.
conjf()	Conjugate, float complex.
conjl()	Conjugate, long double complex.

4.6.2.1.1. cabs()

Description

Compute magnitude, double complex.

Prototype

double cabs(__SEGGER_RTL_FLOAT64_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute magnitude of.

Return value

The magnitude of x, |x|.

4.6.2.1.2. cabsf()

Description

Compute magnitude, float complex.

Prototype

float cabsf(__SEGGER_RTL_FLOAT32_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute magnitude of.

Return value

The magnitude of x, |x|.

4.6.2.1.3. cabsl()

Description

Compute magnitude, long double complex.

Prototype

long double cabsl(__SEGGER_RTL_LDOUBLE_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute magnitude of.

Return value

The magnitude of x, |x|.

4.6.2.1.4. carg()

Description

Compute phase, double complex.

Prototype

double carg(__SEGGER_RTL_FLOAT64_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute phase of.

Return value

The phase of x.

4.6.2.1.5. cargf()

Description

Compute phase, float complex.

Prototype

float cargf(__SEGGER_RTL_FLOAT32_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute phase of.

Return value

The phase of x.

4.6.2.1.6. cargl()

Description

Compute phase, long double complex.

Prototype

long double cargl(__SEGGER_RTL_LDOUBLE_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute phase of.

Return value

The phase of x.

4.6.2.1.7. cimag()

Description

Imaginary part, double complex.

Prototype

double cimag(__SEGGER_RTL_FLOAT64_C_COMPLEX x);

Parameters

Parameter	Description
x	Argument.

Return value

The imaginary part of the complex value.

4.6.2.1.8. cimagf()

Description

Imaginary part, float complex.

Prototype

float cimagf(__SEGGER_RTL_FLOAT32_C_COMPLEX x);

Parameters

Parameter	Description
x	Argument.

Return value

The imaginary part of the complex value.

4.6.2.1.9. cimagl()

Description

Imaginary part, long double complex.

Prototype

long double cimagl(__SEGGER_RTL_LDOUBLE_C_COMPLEX x);

Parameters

Parameter	Description
x	Argument.

Return value

The imaginary part of the complex value.

4.6.2.1.10. creal()

Description

Real part, double complex.

Prototype

double creal(__SEGGER_RTL_FLOAT64_C_COMPLEX x);

Parameters

Parameter	Description
x	Argument.

Return value

The real part of the complex value.

4.6.2.1.11. crealf()

Description

Real part, float complex.

Prototype

float crealf(__SEGGER_RTL_FLOAT32_C_COMPLEX x);

Parameters

Parameter	Description
x	Argument.

Return value

The real part of the complex value.

4.6.2.1.12. creall()

Description

Real part, long double complex.

Prototype

long double creall(__SEGGER_RTL_LDOUBLE_C_COMPLEX x);

Parameters

Parameter	Description
x	Argument.

Return value

The real part of the complex value.

4.6.2.1.13. cproj()

Description

Project, double complex.

Prototype

__SEGGER_RTL_FLOAT64_C_COMPLEX cproj(__SEGGER_RTL_FLOAT64_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to project.

Return value

The projection of x to the Reimann sphere.

Additional information

x projects to x, except that all complex infinities (even those with one infinite part and one NaN part) project to positive infinity on the real axis. If x has an infinite part, then cproj(x) is be equivalent to:

INFINITY + I * copysign(0.0, cimag(x))

4.6.2.1.14. cprojf()

Description

Project, float complex.

Prototype

__SEGGER_RTL_FLOAT32_C_COMPLEX cprojf(__SEGGER_RTL_FLOAT32_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to project.

Return value

The projection of x to the Reimann sphere.

Additional information

x projects to x, except that all complex infinities (even those with one infinite part and one NaN part) project to positive infinity on the real axis. If x has an infinite part, then cproj(x) is be equivalent to:

INFINITY + I * copysign(0.0, cimag(x))

4.6.2.1.15. cprojl()

Description

Project, long double complex.

Prototype

__SEGGER_RTL_LDOUBLE_C_COMPLEX cprojl(__SEGGER_RTL_LDOUBLE_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to project.

Return value

The projection of x to the Reimann sphere.

Additional information

x projects to x, except that all complex infinities (even those with one infinite part and one NaN part) project to positive infinity on the real axis. If x has an infinite part, then cproj(x) is be equivalent to:

INFINITY + I * copysignl(0.0, cimagl(x))

4.6.2.1.16. conj()

Description

Conjugate, double complex.

Prototype

__SEGGER_RTL_FLOAT64_C_COMPLEX conj(__SEGGER_RTL_FLOAT64_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to conjugate.

Return value

The complex conjugate of x.

4.6.2.1.17. conjf()

Description

Conjugate, float complex.

Prototype

__SEGGER_RTL_FLOAT32_C_COMPLEX conjf(__SEGGER_RTL_FLOAT32_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to conjugate.

Return value

The complex conjugate of x.

4.6.2.1.18. conjl()

Description

Conjugate, long double complex.

Prototype

__SEGGER_RTL_LDOUBLE_C_COMPLEX conjl(__SEGGER_RTL_LDOUBLE_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to conjugate.

Return value

The complex conjugate of x.

4.6.2.2. Trigonometric functions

Function	Description
csin()	Compute sine, double complex.
csinf()	Compute sine, float complex.
csinl()	Compute sine, long double complex.
ccos()	Compute cosine, double complex.
ccosf()	Compute cosine, float complex.
ccosl()	Compute cosine, long double complex.
ctan()	Compute tangent, double complex.
ctanf()	Compute tangent, float complex.
ctanl()	Compute tangent, long double complex.
casin()	Compute inverse sine, double complex.
casinf()	Compute inverse sine, float complex.
casinl()	Compute inverse sine, long double complex.
cacos()	Compute inverse cosine, double complex.
cacosf()	Compute inverse cosine, float complex.
cacosl()	Compute inverse cosine, long double complex.
catan()	Compute inverse tangent, double complex.
catanf()	Compute inverse tangent, float complex.
catanl()	Compute inverse tangent, long double complex.

4.6.2.2.1. csin()

Description

Compute sine, double complex.

Prototype

__SEGGER_RTL_FLOAT64_C_COMPLEX csin(__SEGGER_RTL_FLOAT64_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute sine of.

Return value

The sine of x.

4.6.2.2.2. csinf()

Description

Compute sine, float complex.

Prototype

__SEGGER_RTL_FLOAT32_C_COMPLEX csinf(__SEGGER_RTL_FLOAT32_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute sine of.

Return value

The sine of x.

4.6.2.2.3. csinl()

Description

Compute sine, long double complex.

Prototype

__SEGGER_RTL_LDOUBLE_C_COMPLEX csinl(__SEGGER_RTL_LDOUBLE_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute sine of.

Return value

The sine of x.

4.6.2.2.4. ccos()

Description

Compute cosine, double complex.

Prototype

__SEGGER_RTL_FLOAT64_C_COMPLEX ccos(__SEGGER_RTL_FLOAT64_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute cosine of.

Return value

The cosine of x.

4.6.2.2.5. ccosf()

Description

Compute cosine, float complex.

Prototype

__SEGGER_RTL_FLOAT32_C_COMPLEX ccosf(__SEGGER_RTL_FLOAT32_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute cosine of.

Return value

The cosine of x.

4.6.2.2.6. ccosl()

Description

Compute cosine, long double complex.

Prototype

__SEGGER_RTL_LDOUBLE_C_COMPLEX ccosl(__SEGGER_RTL_LDOUBLE_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute cosine of.

Return value

The cosine of x.

4.6.2.2.7. ctan()

Description

Compute tangent, double complex.

Prototype

__SEGGER_RTL_FLOAT64_C_COMPLEX ctan(__SEGGER_RTL_FLOAT64_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute tangent of.

Return value

The tangent of x.

4.6.2.2.8. ctanf()

Description

Compute tangent, float complex.

Prototype

__SEGGER_RTL_FLOAT32_C_COMPLEX ctanf(__SEGGER_RTL_FLOAT32_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute tangent of.

Return value

The tangent of x.

4.6.2.2.9. ctanl()

Description

Compute tangent, long double complex.

Prototype

__SEGGER_RTL_LDOUBLE_C_COMPLEX ctanl(__SEGGER_RTL_LDOUBLE_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute tangent of.

Return value

The tangent of x.

4.6.2.2.10. casin()

Description

Compute inverse sine, double complex.

Prototype

__SEGGER_RTL_FLOAT64_C_COMPLEX casin(__SEGGER_RTL_FLOAT64_C_COMPLEX x);

Parameters

Parameter	Description
x	Argument.

Return value

Inverse sine of x.

Notes

casin(z) = -i casinh(i.z)

4.6.2.2.11. casinf()

Description

Compute inverse sine, float complex.

Prototype

__SEGGER_RTL_FLOAT32_C_COMPLEX casinf(__SEGGER_RTL_FLOAT32_C_COMPLEX x);

Parameters

Parameter	Description
x	Argument.

Return value

Inverse sine of x.

Notes

casin(z) = -i casinh(i.z)

4.6.2.2.12. casinl()

Description

Compute inverse sine, long double complex.

Prototype

__SEGGER_RTL_LDOUBLE_C_COMPLEX casinl(__SEGGER_RTL_LDOUBLE_C_COMPLEX x);

Parameters

Parameter	Description
x	Argument.

Return value

Inverse sine of x.

Notes

casinl(z) = -i casinhl(i.z)

4.6.2.2.13. cacos()

Description

Compute inverse cosine, double complex.

Prototype

__SEGGER_RTL_FLOAT64_C_COMPLEX cacos(__SEGGER_RTL_FLOAT64_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute inverse cosine of.

Return value

The inverse cosine of x.

4.6.2.2.14. cacosf()

Description

Compute inverse cosine, float complex.

Prototype

__SEGGER_RTL_FLOAT32_C_COMPLEX cacosf(__SEGGER_RTL_FLOAT32_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute inverse cosine of.

Return value

The inverse cosine of x.

4.6.2.2.15. cacosl()

Description

Compute inverse cosine, long double complex.

Prototype

__SEGGER_RTL_LDOUBLE_C_COMPLEX cacosl(__SEGGER_RTL_LDOUBLE_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute inverse cosine of.

Return value

The inverse cosine of x.

4.6.2.2.16. catan()

Description

Compute inverse tangent, double complex.

Prototype

__SEGGER_RTL_FLOAT64_C_COMPLEX catan(__SEGGER_RTL_FLOAT64_C_COMPLEX x);

Parameters

Parameter	Description
x	Argument.

Return value

Inverse tangent of x.

Notes

catan(z) = -i catanh(i.z)

4.6.2.2.17. catanf()

Description

Compute inverse tangent, float complex.

Prototype

__SEGGER_RTL_FLOAT32_C_COMPLEX catanf(__SEGGER_RTL_FLOAT32_C_COMPLEX x);

Parameters

Parameter	Description
x	Argument.

Return value

Inverse tangent of x.

Notes

catan(z) = -i catanh(i.z)

4.6.2.2.18. catanl()

Description

Compute inverse tangent, long double complex.

Prototype

__SEGGER_RTL_LDOUBLE_C_COMPLEX catanl(__SEGGER_RTL_LDOUBLE_C_COMPLEX x);

Parameters

Parameter	Description
x	Argument.

Return value

Inverse tangent of x.

Notes

catanl(z) = -i catanhl(i.z)

4.6.2.3. Hyperbolic functions

Function	Description
csinh()	Compute hyperbolic sine, double complex.
csinhf()	Compute hyperbolic sine, float complex.
csinhl()	Compute hyperbolic sine, long double complex.
ccosh()	Compute hyperbolic cosine, double complex.
ccoshf()	Compute hyperbolic cosine, float complex.
ccoshl()	Compute hyperbolic cosine, long double complex.
ctanh()	Compute hyperbolic tangent, double complex.
ctanhf()	Compute hyperbolic tangent, float complex.
ctanhl()	Compute hyperbolic tangent, long double complex.
casinh()	Compute inverse hyperbolic sine, double complex.
casinhf()	Compute inverse hyperbolic sine, float complex.
casinhl()	Compute inverse hyperbolic sine, long double complex.
cacosh()	Compute inverse hyperbolic cosine, double complex.
cacoshf()	Compute inverse hyperbolic cosine, float complex.
cacoshl()	Compute inverse hyperbolic cosine, long double complex.
catanh()	Compute inverse hyperbolic tangent, double complex.
catanhf()	Compute inverse hyperbolic tangent, float complex.
catanhl()	Compute inverse hyperbolic tangent, long double complex.

4.6.2.3.1. csinh()

Description

Compute hyperbolic sine, double complex.

Prototype

__SEGGER_RTL_FLOAT64_C_COMPLEX csinh(__SEGGER_RTL_FLOAT64_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute hyperbolic sine of.

Return value

The hyperbolic sine of x according to the following table:

Argument	csinh(Argument)
+0 + 0i	+0 + 0i
+0 + ∞i	±0 + NaNi, sign of real part unspecified
+0 + NaNi	±0 + NaNi, sign of real part unspecified
a + ∞i	NaN + NaNi, for positive finite a
a + NaNi	NaN + NaNi, for finite nonzero a
+∞ + 0i	+∞ + 0i
+∞ + bi	+∞×cos(b) + +∞×sin(b).i for positive finite b
+∞ + ∞i	±∞ + NaNi, sign of real part unspecified
+∞ + NaNi	±∞ + NaNi, sign of real part unspecified
NaN + 0i	NaN + 0i
NaN + bi	NaN + NaNi, for all nonzero b
NaN + NaNi	NaN + NaNi

For arguments with a negative imaginary component, use the equality:

csinh(conj(z)) = conj(csinh(z)).

For arguments with a negative real component, use the equality:

csinh(-z) = -csinh(z).

4.6.2.3.2. csinhf()

Description

Compute hyperbolic sine, float complex.

Prototype

__SEGGER_RTL_FLOAT32_C_COMPLEX csinhf(__SEGGER_RTL_FLOAT32_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute hyperbolic sine of.

Return value

The hyperbolic sine of x according to the following table:

Argument	csinh(Argument)
+0 + 0i	+0 + 0i
+0 + ∞i	±0 + NaNi, sign of real part unspecified
+0 + NaNi	±0 + NaNi, sign of real part unspecified
a + ∞i	NaN + NaNi, for positive finite a
a + NaNi	NaN + NaNi, for finite nonzero a
+∞ + 0i	+∞ + 0i
+∞ + bi	+∞×cos(b) + +∞×sin(b).i for positive finite b
+∞ + ∞i	±∞ + NaNi, sign of real part unspecified
+∞ + NaNi	±∞ + NaNi, sign of real part unspecified
NaN + 0i	NaN + 0i
NaN + bi	NaN + NaNi, for all nonzero b
NaN + NaNi	NaN + NaNi

For arguments with a negative imaginary component, use the equality:

csinh(conj(z)) = conj(csinh(z)).

For arguments with a negative real component, use the equality:

csinh(-z) = -csinh(z).

4.6.2.3.3. csinhl()

Description

Compute hyperbolic sine, long double complex.

Prototype

__SEGGER_RTL_LDOUBLE_C_COMPLEX csinhl(__SEGGER_RTL_LDOUBLE_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute hyperbolic sine of.

Return value

The hyperbolic sine of x according to the following table:

Argument	csinh(Argument)
+0 + 0i	+0 + 0i
+0 + ∞i	±0 + NaNi, sign of real part unspecified
+0 + NaNi	±0 + NaNi, sign of real part unspecified
a + ∞i	NaN + NaNi, for positive finite a
a + NaNi	NaN + NaNi, for finite nonzero a
+∞ + 0i	+∞ + 0i
+∞ + bi	+∞×cos(b) + +∞×sin(b).i for positive finite b
+∞ + ∞i	±∞ + NaNi, sign of real part unspecified
+∞ + NaNi	±∞ + NaNi, sign of real part unspecified
NaN + 0i	NaN + 0i
NaN + bi	NaN + NaNi, for all nonzero b
NaN + NaNi	NaN + NaNi

For arguments with a negative imaginary component, use the equality:

csinh(conj(z)) = conj(csinh(z)).

For arguments with a negative real component, use the equality:

csinh(-z) = -csinh(z).

4.6.2.3.4. ccosh()

Description

Compute hyperbolic cosine, double complex.

Prototype

__SEGGER_RTL_FLOAT64_C_COMPLEX ccosh(__SEGGER_RTL_FLOAT64_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute hyperbolic cosine of.

Return value

The hyperbolic cosine of x according to the following table:

Argument	ccosh(Argument)
+0 + 0i	+1 + 0i
+0 + ∞i	NaN + ±0i, sign of imaginary part unspecified
+0 + NaNi	NaN + ±0i, sign of imaginary part unspecified
a + ∞i	NaN + NaNi, for finite nonzero a
a + NaNi	NaN + NaNi, for finite nonzero a
+∞ + 0i	+∞ + 0i
+∞ + bi	+∞×cos(b) + Inf×sin(b).i for finite nonzero b
+∞ + ∞i	+∞ + NaNi
+∞ + NaNi	+∞ + NaNi
NaN + 0i	NaN + ±0i, sign of imaginary part unspecified
NaN + bi	NaN + NaNi, for all nonzero b
NaN + NaNi	NaN + NaNi

For arguments with a negative imaginary component, use the equality:

ccosh(conj(z)) = conj(ccosh(z)).

4.6.2.3.5. ccoshf()

Description

Compute hyperbolic cosine, float complex.

Prototype

__SEGGER_RTL_FLOAT32_C_COMPLEX ccoshf(__SEGGER_RTL_FLOAT32_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute hyperbolic cosine of.

Return value

The hyperbolic cosine of x according to the following table:

Argument	ccosh(Argument)
+0 + 0i	+1 + 0i
+0 + ∞i	NaN + ±0i, sign of imaginary part unspecified
+0 + NaNi	NaN + ±0i, sign of imaginary part unspecified
a + ∞i	NaN + NaNi, for finite nonzero a
a + NaNi	NaN + NaNi, for finite nonzero a
+∞ + 0i	+∞ + 0i
+∞ + bi	+∞×cos(b) + Inf×sin(b).i for finite nonzero b
+∞ + ∞i	+∞ + NaNi
+∞ + NaNi	+∞ + NaNi
NaN + 0i	NaN + ±0i, sign of imaginary part unspecified
NaN + bi	NaN + NaNi, for all nonzero b
NaN + NaNi	NaN + NaNi

For arguments with a negative imaginary component, use the equality:

ccosh(conj(z)) = conj(ccosh(z)).

4.6.2.3.6. ccoshl()

Description

Compute hyperbolic cosine, long double complex.

Prototype

__SEGGER_RTL_LDOUBLE_C_COMPLEX ccoshl(__SEGGER_RTL_LDOUBLE_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute hyperbolic cosine of.

Return value

The hyperbolic cosine of x according to the following table:

Argument	ccosh(Argument)
+0 + 0i	+1 + 0i
+0 + ∞i	NaN + ±0i, sign of imaginary part unspecified
+0 + NaNi	NaN + ±0i, sign of imaginary part unspecified
a + ∞i	NaN + NaNi, for finite nonzero a
a + NaNi	NaN + NaNi, for finite nonzero a
+∞ + 0i	+∞ + 0i
+∞ + bi	+∞×cos(b) + Inf×sin(b).i for finite nonzero b
+∞ + ∞i	+∞ + NaNi
+∞ + NaNi	+∞ + NaNi
NaN + 0i	NaN + ±0i, sign of imaginary part unspecified
NaN + bi	NaN + NaNi, for all nonzero b
NaN + NaNi	NaN + NaNi

For arguments with a negative imaginary component, use the equality:

ccosh(conj(z)) = conj(ccosh(z)).

4.6.2.3.7. ctanh()

Description

Compute hyperbolic tangent, double complex.

Prototype

__SEGGER_RTL_FLOAT64_C_COMPLEX ctanh(__SEGGER_RTL_FLOAT64_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute hyperbolic tangent of.

Return value

The hyperbolic tangent of x according to the following table:

Argument	ctanh(Argument)
+0 + 0i	+0 + 0i
a + ∞i	NaN + NaNi, for finite a
a + NaNi	NaN + NaNi, for finite a
+∞ + bi	+1 + sin(2b)×0i for positive-signed finite b
+∞ + ∞i	+1 + ±0i, sign of imaginary part unspecified
+∞ + NaNi	+1 + ±0i, sign of imaginary part unspecified
NaN + 0i	NaN + 0i
NaN + bi	NaN + NaNi, for all nonzero b
NaN + NaNi	NaN + NaNi

For arguments with a negative imaginary component, use the equality:

ctanh(conj(z)) = conj(ctanh(z)).

For arguments with a negative real component, use the equality:

ctanh(-z) = -ctanh(z).

4.6.2.3.8. ctanhf()

Description

Compute hyperbolic tangent, float complex.

Prototype

__SEGGER_RTL_FLOAT32_C_COMPLEX ctanhf(__SEGGER_RTL_FLOAT32_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute hyperbolic tangent of.

Return value

The hyperbolic tangent of x according to the following table:

Argument	ctanh(Argument)
+0 + 0i	+0 + 0i
a + ∞i	NaN + NaNi, for finite a
a + NaNi	NaN + NaNi, for finite a
+∞ + bi	+1 + sin(2b)×0i for positive-signed finite b
+∞ + ∞i	+1 + ±0i, sign of imaginary part unspecified
+∞ + NaNi	+1 + ±0i, sign of imaginary part unspecified
NaN + 0i	NaN + 0i
NaN + bi	NaN + NaNi, for all nonzero b
NaN + NaNi	NaN + NaNi

For arguments with a negative imaginary component, use the equality:

ctanhf(conj(z)) = conj(ctanhf(z)).

For arguments with a negative real component, use the equality:

ctanhf(-z) = -ctanhf(z).

4.6.2.3.9. ctanhl()

Description

Compute hyperbolic tangent, long double complex.

Prototype

__SEGGER_RTL_LDOUBLE_C_COMPLEX ctanhl(__SEGGER_RTL_LDOUBLE_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute hyperbolic tangent of.

Return value

The hyperbolic tangent of x according to the following table:

Argument	ctanh(Argument)
+0 + 0i	+0 + 0i
a + ∞i	NaN + NaNi, for finite a
a + NaNi	NaN + NaNi, for finite a
+∞ + bi	+1 + sin(2b)×0i for positive-signed finite b
+∞ + ∞i	+1 + ±0i, sign of imaginary part unspecified
+∞ + NaNi	+1 + ±0i, sign of imaginary part unspecified
NaN + 0i	NaN + 0i
NaN + bi	NaN + NaNi, for all nonzero b
NaN + NaNi	NaN + NaNi

For arguments with a negative imaginary component, use the equality:

ctanh(conj(z)) = conj(ctanh(z)).

For arguments with a negative real component, use the equality:

ctanh(-z) = -ctanh(z).

4.6.2.3.10. casinh()

Description

Compute inverse hyperbolic sine, double complex.

Prototype

__SEGGER_RTL_FLOAT64_C_COMPLEX casinh(__SEGGER_RTL_FLOAT64_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute inverse hyperbolic sineof.

Return value

The inverse hyperbolic sine of x according to the following table:

Argument	casinh(Argument)
+0 + 0i	+0 + 0i
+0 + ∞i	+∞ + ½πi
a + NaNi	NaN + NaNi
+∞ + bi	+∞ + 0i, for positive-signed b
+∞ + ∞i	+Pi + 0i
+∞ + NaNi	+∞ + NaNi
NaN + 0i	NaN + 0i
NaN + bi	NaN + NaNi, for finite nonzero b
NaN + ∞i	±∞ + NaNi, sign of real part unspecified
NaN + NaNi	NaN + NaNi

For arguments with a negative imaginary component, use the equality:

casinh(conj(z)) = conj(casinh(z)).

For arguments with a negative real component, use the equality:

casinh(-z) = -casinh(z).

4.6.2.3.11. casinhf()

Description

Compute inverse hyperbolic sine, float complex.

Prototype

__SEGGER_RTL_FLOAT32_C_COMPLEX casinhf(__SEGGER_RTL_FLOAT32_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute inverse hyperbolic sineof.

Return value

The inverse hyperbolic sine of x according to the following table:

Argument	casinh(Argument)
+0 + 0i	+0 + 0i
+0 + ∞i	+∞ + ½πi
a + NaNi	NaN + NaNi
+∞ + bi	+∞ + 0i, for positive-signed b
+∞ + ∞i	+Pi + 0i
+∞ + NaNi	+∞ + NaNi
NaN + 0i	NaN + 0i
NaN + bi	NaN + NaNi, for finite nonzero b
NaN + ∞i	±∞ + NaNi, sign of real part unspecified
NaN + NaNi	NaN + NaNi

For arguments with a negative imaginary component, use the equality:

casinh(conj(z)) = conj(casinh(z)).

For arguments with a negative real component, use the equality:

casinh(-z) = -casinh(z).

4.6.2.3.12. casinhl()

Description

Compute inverse hyperbolic sine, long double complex.

Prototype

__SEGGER_RTL_LDOUBLE_C_COMPLEX casinhl(__SEGGER_RTL_LDOUBLE_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute inverse hyperbolic sineof.

Return value

The inverse hyperbolic sine of x according to the following table:

Argument	casinh(Argument)
+0 + 0i	+0 + 0i
+0 + ∞i	+∞ + ½πi
a + NaNi	NaN + NaNi
+∞ + bi	+∞ + 0i, for positive-signed b
+∞ + ∞i	+Pi + 0i
+∞ + NaNi	+∞ + NaNi
NaN + 0i	NaN + 0i
NaN + bi	NaN + NaNi, for finite nonzero b
NaN + ∞i	±∞ + NaNi, sign of real part unspecified
NaN + NaNi	NaN + NaNi

For arguments with a negative imaginary component, use the equality:

casinh(conj(z)) = conj(casinh(z)).

For arguments with a negative real component, use the equality:

casinh(-z) = -casinh(z).

4.6.2.3.13. cacosh()

Description

Compute inverse hyperbolic cosine, double complex.

Prototype

__SEGGER_RTL_FLOAT64_C_COMPLEX cacosh(__SEGGER_RTL_FLOAT64_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute inverse hyperbolic cosine of.

Return value

The inverse hyperbolic cosine of x according to the following table:

Argument	cacosh(Argument)
±0 + 0i	+0 + 0i
a + ∞i	+∞ + ½πi, for finite a
a + NaNi	NaN + NaNi, for finite a
-∞ + bi	+∞ + πi, for positive-signed finite b
+∞ + bi	+∞ + 0i, for positive-signed finite b
-∞ + ∞i	±∞ + ¾πi
+∞ + ∞i	±∞ + ¼πi
±∞ + NaNi	+∞ + NaNi
NaN + bi	NaN + NaNi, for finite b
NaN + ∞i	+∞ + NaNi
NaN + NaNi	NaN + NaNi

For arguments with a negative imaginary component, use the equality:

cacosh(conj(z)) = conj(cacosh(z)).

4.6.2.3.14. cacoshf()

Description

Compute inverse hyperbolic cosine, float complex.

Prototype

__SEGGER_RTL_FLOAT32_C_COMPLEX cacoshf(__SEGGER_RTL_FLOAT32_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute inverse hyperbolic cosine of.

Return value

The inverse hyperbolic cosine of x according to the following table:

Argument	cacosh(Argument)
±0 + 0i	+0 + 0i
a + ∞i	+∞ + ½πi, for finite a
a + NaNi	NaN + NaNi, for finite a
-∞ + bi	+∞ + πi, for positive-signed finite b
+∞ + bi	+∞ + 0i, for positive-signed finite b
-∞ + ∞i	±∞ + ¾πi
+∞ + ∞i	±∞ + ¼πi
±∞ + NaNi	+∞ + NaNi
NaN + bi	NaN + NaNi, for finite b
NaN + ∞i	+∞ + NaNi
NaN + NaNi	NaN + NaNi

For arguments with a negative imaginary component, use the equality:

cacosh(conj(z)) = conj(cacosh(z)).

4.6.2.3.15. cacoshl()

Description

Compute inverse hyperbolic cosine, long double complex.

Prototype

__SEGGER_RTL_LDOUBLE_C_COMPLEX cacoshl(__SEGGER_RTL_LDOUBLE_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute inverse hyperbolic cosine of.

Return value

The inverse hyperbolic cosine of x according to the following table:

Argument	cacosh(Argument)
±0 + 0i	+0 + 0i
a + ∞i	+∞ + ½πi, for finite a
a + NaNi	NaN + NaNi, for finite a
-∞ + bi	+∞ + πi, for positive-signed finite b
+∞ + bi	+∞ + 0i, for positive-signed finite b
-∞ + ∞i	±∞ + ¾πi
+∞ + ∞i	±∞ + ¼πi
±∞ + NaNi	+∞ + NaNi
NaN + bi	NaN + NaNi, for finite b
NaN + ∞i	+∞ + NaNi
NaN + NaNi	NaN + NaNi

For arguments with a negative imaginary component, use the equality:

cacosh(conj(z)) = conj(cacosh(z)).

4.6.2.3.16. catanh()

Description

Compute inverse hyperbolic tangent, double complex.

Prototype

__SEGGER_RTL_FLOAT64_C_COMPLEX catanh(__SEGGER_RTL_FLOAT64_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute inverse hyperbolic tangent of.

Return value

The inverse hyperbolic tangent of x according to the following table:

Argument	catanh(Argument)
+0 + 0i	+0 + 0i
+0 + NaNi	+0 + NaNi
+1 + 0i	+∞ + 0i
a + ∞i	+0 + ½πi for positive-signed a
a + NaNi	NaN + NaNi, for nonzero finite a
+∞ + bi	+0 + ½πi for positive-signed b
+∞ + ∞i	+0 + ½πi
+∞ + NaNi	+0 + NaNi
NaN + bi	NaN + NaNi, for finite b
NaN + NaNi	NaN + NaNi

For arguments with a negative imaginary component, use the equality:

catanh(conj(z)) = conj(catanh(z)).

For arguments with a negative real component, use the equality:

catanh(-z) = -catanh(z).

4.6.2.3.17. catanhf()

Description

Compute inverse hyperbolic tangent, float complex.

Prototype

__SEGGER_RTL_FLOAT32_C_COMPLEX catanhf(__SEGGER_RTL_FLOAT32_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute inverse hyperbolic tangent of.

Return value

The inverse hyperbolic tangent of x according to the following table:

Argument	catanh(Argument)
+0 + 0i	+0 + 0i
+0 + NaNi	+0 + NaNi
+1 + 0i	+∞ + 0i
a + ∞i	+0 + ½πi for positive-signed a
a + NaNi	NaN + NaNi, for nonzero finite a
+∞ + bi	+0 + ½πi for positive-signed b
+∞ + ∞i	+0 + ½πi
+∞ + NaNi	+0 + NaNi
NaN + bi	NaN + NaNi, for finite b
NaN + NaNi	NaN + NaNi

For arguments with a negative imaginary component, use the equality:

catanh(conj(z)) = conj(catanh(z)).

For arguments with a negative real component, use the equality:

catanh(-z) = -catanh(z).

4.6.2.3.18. catanhl()

Description

Compute inverse hyperbolic tangent, long double complex.

Prototype

__SEGGER_RTL_LDOUBLE_C_COMPLEX catanhl(__SEGGER_RTL_LDOUBLE_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute inverse hyperbolic tangent of.

Return value

The inverse hyperbolic tangent of x according to the following table:

Argument	catanh(Argument)
+0 + 0i	+0 + 0i
+0 + NaNi	+0 + NaNi
+1 + 0i	+∞ + 0i
a + ∞i	+0 + ½πi for positive-signed a
a + NaNi	NaN + NaNi, for nonzero finite a
+∞ + bi	+0 + ½πi for positive-signed b
+∞ + ∞i	+0 + ½πi
+∞ + NaNi	+0 + NaNi
NaN + bi	NaN + NaNi, for finite b
NaN + NaNi	NaN + NaNi

For arguments with a negative imaginary component, use the equality:

catanh(conj(z)) = conj(catanh(z)).

For arguments with a negative real component, use the equality:

catanh(-z) = -catanh(z).

4.6.2.4. Power and absolute value

Function	Description
cabs()	Compute magnitude, double complex.
cabsf()	Compute magnitude, float complex.
cabsl()	Compute magnitude, long double complex.
cpow()	Power, double complex.
cpowf()	Power, float complex.
cpowl()	Power, long double complex.
csqrt()	Square root, double complex.
csqrtf()	Square root, float complex.
csqrtl()	Square root, long double complex.

4.6.2.4.1. cabs()

Description

Compute magnitude, double complex.

Prototype

double cabs(__SEGGER_RTL_FLOAT64_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute magnitude of.

Return value

The magnitude of x, |x|.

4.6.2.4.2. cabsf()

Description

Compute magnitude, float complex.

Prototype

float cabsf(__SEGGER_RTL_FLOAT32_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute magnitude of.

Return value

The magnitude of x, |x|.

4.6.2.4.3. cabsl()

Description

Compute magnitude, long double complex.

Prototype

long double cabsl(__SEGGER_RTL_LDOUBLE_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute magnitude of.

Return value

The magnitude of x, |x|.

4.6.2.4.4. cpow()

Description

Power, double complex.

Prototype

__SEGGER_RTL_FLOAT64_C_COMPLEX cpow(__SEGGER_RTL_FLOAT64_C_COMPLEX x,
                                    __SEGGER_RTL_FLOAT64_C_COMPLEX y);

Parameters

Parameter	Description
x	Base.
y	Power.

Return value

Return x raised to the power of y.

4.6.2.4.5. cpowf()

Description

Power, float complex.

Prototype

__SEGGER_RTL_FLOAT32_C_COMPLEX cpowf(__SEGGER_RTL_FLOAT32_C_COMPLEX x,
                                     __SEGGER_RTL_FLOAT32_C_COMPLEX y);

Parameters

Parameter	Description
x	Base.
y	Power.

Return value

Return x raised to the power of y.

4.6.2.4.6. cpowl()

Description

Power, long double complex.

Prototype

__SEGGER_RTL_LDOUBLE_C_COMPLEX cpowl(__SEGGER_RTL_LDOUBLE_C_COMPLEX x,
                                     __SEGGER_RTL_LDOUBLE_C_COMPLEX y);

Parameters

Parameter	Description
x	Base.
y	Power.

Return value

Return x raised to the power of y.

4.6.2.4.7. csqrt()

Description

Square root, double complex.

Prototype

__SEGGER_RTL_FLOAT64_C_COMPLEX csqrt(__SEGGER_RTL_FLOAT64_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute squate root of.

Return value

The square root of x according to the following table:

Argument	csqrt(Argument)
±0 + 0i	+0 + 0i
a + ∞i	+∞ + ∞i, for all a
a + NaNi	+NaN + NaNi, for finite a
-∞ + bi	+0 + ∞i for finite positive-signed b
+∞ + bi	+∞ + 0i, for finite positive-signed b
+∞ + ∞i	+∞ + ¼πi
-∞ + NaNi	+NaN + +/∞i, sign of imaginary part unspecified
+∞ + NaNi	+∞ + NaNi
NaN + bi	NaN + NaNi, for finite b
NaN + ∞i	+∞ + ∞i
NaN + NaNi	NaN + NaNi

For arguments with a negative imaginary component, use the equality:

csqrt(conj(z)) = conj(csqrt(z)).

4.6.2.4.8. csqrtf()

Description

Square root, float complex.

Prototype

__SEGGER_RTL_FLOAT32_C_COMPLEX csqrtf(__SEGGER_RTL_FLOAT32_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute squate root of.

Return value

The square root of x according to the following table:

Argument	csqrt(Argument)
±0 + 0i	+0 + 0i
a + ∞i	+∞ + ∞i, for all a
a + NaNi	+NaN + NaNi, for finite a
-∞ + bi	+0 + ∞i for finite positive-signed b
+∞ + bi	+∞ + 0i, for finite positive-signed b
+∞ + ∞i	+∞ + ¼πi
-∞ + NaNi	+NaN + +/∞i, sign of imaginary part unspecified
+∞ + NaNi	+∞ + NaNi
NaN + bi	NaN + NaNi, for finite b
NaN + ∞i	+∞ + ∞i
NaN + NaNi	NaN + NaNi

For arguments with a negative imaginary component, use the equality:

csqrt(conj(z)) = conj(csqrt(z)).

4.6.2.4.9. csqrtl()

Description

Square root, long double complex.

Prototype

__SEGGER_RTL_LDOUBLE_C_COMPLEX csqrtl(__SEGGER_RTL_LDOUBLE_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute squate root of.

Return value

The square root of x according to the following table:

Argument	csqrt(Argument)
±0 + 0i	+0 + 0i
a + ∞i	+∞ + ∞i, for all a
a + NaNi	+NaN + NaNi, for finite a
-∞ + bi	+0 + ∞i for finite positive-signed b
+∞ + bi	+∞ + 0i, for finite positive-signed b
+∞ + ∞i	+∞ + ¼πi
-∞ + NaNi	+NaN + +/∞i, sign of imaginary part unspecified
+∞ + NaNi	+∞ + NaNi
NaN + bi	NaN + NaNi, for finite b
NaN + ∞i	+∞ + ∞i
NaN + NaNi	NaN + NaNi

For arguments with a negative imaginary component, use the equality:

csqrt(conj(z)) = conj(csqrt(z)).

4.6.2.5. Exponential and logarithm functions

Function	Description
clog()	Compute natural logarithm, double complex.
clogf()	Compute natural logarithm, float complex.
clogl()	Compute natural logarithm, long double complex.
cexp()	Compute base-e exponential, double complex.
cexpf()	Compute base-e exponential, float complex.
cexpl()	Compute base-e exponential, long double complex.

4.6.2.5.1. clog()

Description

Compute natural logarithm, double complex.

Prototype

__SEGGER_RTL_FLOAT64_C_COMPLEX clog(__SEGGER_RTL_FLOAT64_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute logarithm of.

Return value

The natural logarithm of x according to the following table:

Argument	clog(Argument)
-0 + 0i	-∞ + πi
+0 + 0i	-∞ + 0i
a + ∞i	+∞ + ½πi, for finite a
a + NaNi	NaN + NaNi, for finite a
-∞ + bi	+∞ + πi, for finite positive b
+∞ + bi	+∞ + 0i, for finite positive b
-∞ + ∞i	+∞ + ¾πi
+∞ + ∞i	+∞ + ¼πi
±∞ + NaNi	+∞ + NaNi
NaN + bi	NaN + NaNi, for finite b
NaN + ∞i	+∞ + NaNi
NaN + NaNi	NaN + NaNi

For arguments with a negative imaginary component, use the equality:

clog(conj(z)) = conj(clog(z)).

4.6.2.5.2. clogf()

Description

Compute natural logarithm, float complex.

Prototype

__SEGGER_RTL_FLOAT32_C_COMPLEX clogf(__SEGGER_RTL_FLOAT32_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute logarithm of.

Return value

The natural logarithm of x according to the following table:

Argument	clog(Argument)
-0 + 0i	-∞ + πi
+0 + 0i	-∞ + 0i
a + ∞i	+∞ + ½πi, for finite a
a + NaNi	NaN + NaNi, for finite a
-∞ + bi	+∞ + πi, for finite positive b
+∞ + bi	+∞ + 0i, for finite positive b
-∞ + ∞i	+∞ + ¾πi
+∞ + ∞i	+∞ + ¼πi
±∞ + NaNi	+∞ + NaNi
NaN + bi	NaN + NaNi, for finite b
NaN + ∞i	+∞ + NaNi
NaN + NaNi	NaN + NaNi

For arguments with a negative imaginary component, use the equality:

clog(conj(z)) = conj(clog(z)).

4.6.2.5.3. clogl()

Description

Compute natural logarithm, long double complex.

Prototype

__SEGGER_RTL_LDOUBLE_C_COMPLEX clogl(__SEGGER_RTL_LDOUBLE_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute logarithm of.

Return value

The natural logarithm of x according to the following table:

Argument	clog(Argument)
-0 + 0i	-∞ + πi
+0 + 0i	-∞ + 0i
a + ∞i	+∞ + ½πi, for finite a
a + NaNi	NaN + NaNi, for finite a
-∞ + bi	+∞ + πi, for finite positive b
+∞ + bi	+∞ + 0i, for finite positive b
-∞ + ∞i	+∞ + ¾πi
+∞ + ∞i	+∞ + ¼πi
±∞ + NaNi	+∞ + NaNi
NaN + bi	NaN + NaNi, for finite b
NaN + ∞i	+∞ + NaNi
NaN + NaNi	NaN + NaNi

For arguments with a negative imaginary component, use the equality:

clog(conj(z)) = conj(clog(z)).

4.6.2.5.4. cexp()

Description

Compute base-e exponential, double complex.

Prototype

__SEGGER_RTL_FLOAT64_C_COMPLEX cexp(__SEGGER_RTL_FLOAT64_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute exponential of.

Return value

The base-e exponential of x=a+bi according to the following table:

Argument	cexp(Argument)
-/-0 + 0i	+1 + 0i
a + ∞i	NaN + NaNi, for finite a
a + NaNi	NaN + NaNi, for finite a
+∞ + 0i	+∞ + 0i, for finite positive b
-∞ + bi	+0 cis(b) for finite b
+∞ + bi	+∞ cis(b) for finite nonzero b
-∞ + ∞i	±∞ + ±0i, signs unspecified
+∞ + ∞i	±∞ + i.NaN, sign of real part unspecified
-∞ + NaNi	±0 + ±0i, signs unspecified
+∞ + NaNi	±∞ + NaNi, sign of real part unspecified
NaN + 0i	NaN + 0i
NaN + bi	NaN + NaNi, for nonzero b
NaN + NaNi	NaN + NaNi

For arguments with a negative imaginary component, use the equality

cexp(conj(x)) = conj(cexp(x)).

4.6.2.5.5. cexpf()

Description

Compute base-e exponential, float complex.

Prototype

__SEGGER_RTL_FLOAT32_C_COMPLEX cexpf(__SEGGER_RTL_FLOAT32_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute exponential of.

Return value

The base-e exponential of x=a+bi according to the following table:

Argument	cexp(Argument)
-/-0 + 0i	+1 + 0i
a + ∞i	NaN + NaNi, for finite a
a + NaNi	NaN + NaNi, for finite a
+∞ + 0i	+∞ + 0i, for finite positive b
-∞ + bi	+0 cis(b) for finite b
+∞ + bi	+∞ cis(b) for finite nonzero b
-∞ + ∞i	±∞ + ±0i, signs unspecified
+∞ + ∞i	±∞ + i.NaN, sign of real part unspecified
-∞ + NaNi	±0 + ±0i, signs unspecified
+∞ + NaNi	±∞ + NaNi, sign of real part unspecified
NaN + 0i	NaN + 0i
NaN + bi	NaN + NaNi, for nonzero b
NaN + NaNi	NaN + NaNi

For arguments with a negative imaginary component, use the equality

cexp(conj(x)) = conj(cexp(x)).

4.6.2.5.6. cexpl()

Description

Compute base-e exponential, long double complex.

Prototype

__SEGGER_RTL_LDOUBLE_C_COMPLEX cexpl(__SEGGER_RTL_LDOUBLE_C_COMPLEX x);

Parameters

Parameter	Description
x	Value to compute exponential of.

Return value

The base-e exponential of x=a+bi according to the following table:

Argument	cexp(Argument)
-/-0 + 0i	+1 + 0i
a + ∞i	NaN + NaNi, for finite a
a + NaNi	NaN + NaNi, for finite a
+∞ + 0i	+∞ + 0i, for finite positive b
-∞ + bi	+0 cis(b) for finite b
+∞ + bi	+∞ cis(b) for finite nonzero b
-∞ + ∞i	±∞ + ±0i, signs unspecified
+∞ + ∞i	±∞ + i.NaN, sign of real part unspecified
-∞ + NaNi	±0 + ±0i, signs unspecified
+∞ + NaNi	±∞ + NaNi, sign of real part unspecified
NaN + 0i	NaN + 0i
NaN + bi	NaN + NaNi, for nonzero b
NaN + NaNi	NaN + NaNi

For arguments with a negative imaginary component, use the equality

cexp(conj(x)) = conj(cexp(x)).

4.6.3. <ctype.h>

4.6.3.1. Classification functions

Function	Description
iscntrl()	Is character a control?
iscntrl_l()	Is character a control, per locale? (POSIX.1).
isblank()	Is character a blank?
isblank_l()	Is character a blank, per locale? (POSIX.1).
isspace()	Is character a whitespace character?
isspace_l()	Is character a whitespace character, per locale? (POSIX.1).
ispunct()	Is character a punctuation mark?
ispunct_l()	Is character a punctuation mark, per locale? (POSIX.1).
isdigit()	Is character a decimal digit?
isdigit_l()	Is character a decimal digit, per locale? (POSIX.
isxdigit()	Is character a hexadecimal digit?
isxdigit_l()	Is character a hexadecimal digit, per locale? (POSIX.1).
isalpha()	Is character alphabetic?
isalpha_l()	Is character alphabetic, per locale? (POSIX.1).
isalnum()	Is character alphanumeric?
isalnum_l()	Is character alphanumeric, per locale? (POSIX.1).
isupper()	Is character an uppercase letter?
isupper_l()	Is character an uppercase letter, per locale? (POSIX.1).
islower()	Is character a lowercase letter?
islower_l()	Is character a lowercase letter, per locale? (POSIX.1).
isprint()	Is character printable?
isprint_l()	Is character printable, per locale? (POSIX.1).
isgraph()	Is character any printing character?
isgraph_l()	Is character any printing character, per locale? (POSIX.1).

4.6.3.1.1. iscntrl()

Description

Is character a control?

Prototype

int iscntrl(int c);

Parameters

Parameter	Description
c	Character to test.

Return value

Returns nonzero (true) if and only if the value of the argument c is a control character in the current locale.

4.6.3.1.2. iscntrl_l()

Description

Is character a control, per locale? (POSIX.1).

Prototype

int iscntrl_l(int c,
                  locale_t loc);

Parameters

Parameter	Description
c	Character to test.
loc	Locale used to test c.

Return value

Returns nonzero (true) if and only if the value of the argument c is a control character in the locale loc.

Notes

Conforms to POSIX.1-2017.

4.6.3.1.3. isblank()

Description

Is character a blank?

Prototype

int isblank(int c);

Parameters

Parameter	Description
c	Character to test.

Return value

Returns nonzero (true) if and only if the value of the argument c is either a space character or tab character in the current locale.

4.6.3.1.4. isblank_l()

Description

Is character a blank, per locale? (POSIX.1).

Prototype

int isblank_l(int c,
                  locale_t loc);

Parameters

Parameter	Description
c	Character to test.
loc	Locale used to test c.

Return value

Returns nonzero (true) if and only if the value of the argument c is either a space character or the tab character in locale loc.

Notes

Conforms to POSIX.1-2017.

4.6.3.1.5. isspace()

Description

Is character a whitespace character?

Prototype

int isspace(int c);

Parameters

Parameter	Description
c	Character to test.

Return value

Returns nonzero (true) if and only if the value of the argument c is a standard white-space character in the current locale. The standard white-space characters are space, form feed, new-line, carriage return, horizontal tab, and vertical tab.

4.6.3.1.6. isspace_l()

Description

Is character a whitespace character, per locale? (POSIX.1).

Prototype

int isspace_l(int c, locale_t loc);

Parameters

Parameter	Description
c	Character to test.
loc	Locale used to test c.

Return value

Returns nonzero (true) if and only if the value of the argument c is a standard white-space character in the locale loc.

Notes

Conforms to POSIX.1-2017.

4.6.3.1.7. ispunct()

Description

Is character a punctuation mark?

Prototype

int ispunct(int c);

Parameters

Parameter	Description
c	Character to test.

Return value

Returns nonzero (true) for every printing character for which neither isspace() nor isalnum() is true in the current locale.

4.6.3.1.8. ispunct_l()

Description

Is character a punctuation mark, per locale? (POSIX.1).

Prototype

int ispunct_l(int c, locale_t loc);

Parameters

Parameter	Description
c	Character to test.
loc	Locale used to test c.

Return value

Returns nonzero (true) for every printing character for which neither isspace() nor isalnum() is true in the locale loc.

Notes

Conforms to POSIX.1-2017.

4.6.3.1.9. isdigit()

Description

Is character a decimal digit?

Prototype

int isdigit(int c);

Parameters

Parameter	Description
c	Character to test.

Return value

Returns nonzero (true) if and only if the value of the argument c is a digit in the current locale.

4.6.3.1.10. isdigit_l()

Description

Is character a decimal digit, per locale? (POSIX.1)

Prototype

int isdigit_l(int c, locale_t loc);

Parameters

Parameter	Description
c	Character to test.
loc	Locale used to test c.

Return value

Returns nonzero (true) if and only if the value of the argument c is a digit in the locale loc.

Notes

Conforms to POSIX.1-2017.

4.6.3.1.11. isxdigit()

Description

Is character a hexadecimal digit?

Prototype

int isxdigit(int c);

Parameters

Parameter	Description
c	Character to test.

Return value

Returns nonzero (true) if and only if the value of the argument c is a hexadecimal digit in the current locale.

4.6.3.1.12. isxdigit_l()

Description

Is character a hexadecimal digit, per locale? (POSIX.1).

Prototype

int isxdigit_l(int c, locale_t loc);

Parameters

Parameter	Description
c	Character to test.
loc	Locale used to test c.

Return value

Returns nonzero (true) if and only if the value of the argument c is a hexadecimal digit in the current locale.

Notes

Conforms to POSIX.1-2017.

4.6.3.1.13. isalpha()

Description

Is character alphabetic?

Prototype

int isalpha(int c);

Parameters

Parameter	Description
c	Character to test.

Return value

Returns true if the character c is alphabetic in the current locale. That is, any character for which isupper() or islower() returns true is considered alphabetic in addition to any of the locale-specific set of alphabetic characters for which none of iscntrl(), isdigit(), ispunct(), or isspace() is true.

In the C locale, isalpha() returns nonzero (true) if and only if isupper() or islower() return true for value of the argument c.

4.6.3.1.14. isalpha_l()

Description

Is character alphabetic, per locale? (POSIX.1).

Prototype

int isalpha_l(int c, locale_t loc);

Parameters

Parameter	Description
c	Character to test.
loc	Locale used to test c.

Return value

Returns true if the character c is alphabetic in the locale loc. That is, any character for which isupper() or islower() returns true is considered alphabetic in addition to any of the locale-specific set of alphabetic characters for which none of iscntrl_l(), isdigit_l(), ispunct_l(), or isspace_l() is true in the locale loc.

In the C locale, isalpha_l() returns nonzero (true) if and only if isupper_l() or islower_l() return true for value of the argument c.

Notes

Conforms to POSIX.1-2017.

4.6.3.1.15. isalnum()

Description

Is character alphanumeric?

Prototype

int isalnum(int c);

Parameters

Parameter	Description
c	Character to test.

Return value

Returns nonzero (true) if and only if the value of the argument c is an alphabetic or numeric character in the current locale.

4.6.3.1.16. isalnum_l()

Description

Is character alphanumeric, per locale? (POSIX.1).

Prototype

int isalnum_l(int c, locale_t loc);

Parameters

Parameter	Description
c	Character to test.
loc	Locale used to test c.

Return value

Returns nonzero (true) if and only if the value of the argument c is an alphabetic or numeric character in the locale loc.

Notes

Conforms to POSIX.1-2017.

4.6.3.1.17. isupper()

Description

Is character an uppercase letter?

Prototype

int isupper(int c);

Parameters

Parameter	Description
c	Character to test.

Return value

Returns nonzero (true) if and only if the value of the argument c is an uppercase letter in the current locale.

4.6.3.1.18. isupper_l()

Description

Is character an uppercase letter, per locale? (POSIX.1).

Prototype

int isupper_l(int c, locale_t loc);

Parameters

Parameter	Description
c	Character to test.
loc	Locale used to test c.

Return value

Returns nonzero (true) if and only if the value of the argument c is an uppercase letter in the locale loc.

Notes

Conforms to POSIX.1-2017.

4.6.3.1.19. islower()

Description

Is character a lowercase letter?

Prototype

int islower(int c);

Parameters

Parameter	Description
c	Character to test.

Return value

Returns nonzero (true) if and only if the value of the argument c is a lowercase letter in the current locale.

4.6.3.1.20. islower_l()

Description

Is character a lowercase letter, per locale? (POSIX.1).

Prototype

int islower_l(int c, locale_t loc);

Parameters

Parameter	Description
c	Character to test.
loc	Locale used to test c.

Return value

Returns nonzero (true) if and only if the value of the argument c is a lowercase letter in the locale loc.

Notes

Conforms to POSIX.1-2017.

4.6.3.1.21. isprint()

Description

Is character printable?

Prototype

int isprint(int c);

Parameters

Parameter	Description
c	Character to test.

Return value

Returns nonzero (true) if and only if the value of the argument c is any printing character including space in the current locale.

4.6.3.1.22. isprint_l()

Description

Is character printable, per locale? (POSIX.1).

Prototype

int isprint_l(int c, locale_t loc);

Parameters

Parameter	Description
c	Character to test.
loc	Locale used to test c.

Return value

Returns nonzero (true) if and only if the value of the argument c is any printing character including space in the locale loc.

Notes

Conforms to POSIX.1-2017.

4.6.3.1.23. isgraph()

Description

Is character any printing character?

Prototype

int isgraph(int c);

Parameters

Parameter	Description
c	Character to test.

Return value

Returns nonzero (true) if and only if the value of the argument c is any printing character except space in the current locale.

4.6.3.1.24. isgraph_l()

Description

Is character any printing character, per locale? (POSIX.1).

Prototype

int isgraph_l(int c, locale_t loc);

Parameters

Parameter	Description
c	Character to test.
loc	Locale used to test c.

Return value

Returns nonzero (true) if and only if the value of the argument c is any printing character except space in the locale loc.

Notes

Conforms to POSIX.1-2017.

4.6.3.2. Conversion functions

Function	Description
toupper()	Convert lowercase character to uppercase.
toupper_l()	Convert lowercase character to uppercase, per locale (POSIX.1).
tolower()	Convert uppercase character to lowercase.
tolower_l()	Convert uppercase character to lowercase, per locale (POSIX.1).

4.6.3.2.1. toupper()

Description

Convert lowercase character to uppercase.

Prototype

int toupper(int c);

Parameters

Parameter	Description
c	Character to convert.

Return value

Converted character.

Additional information

Converts a lowercase letter to a corresponding uppercase letter.

If the argument c is a character for which islower() is true and there are one or more corresponding characters, as specified by the current locale, for which isupper() is true, toupper() returns one of the corresponding characters (always the same one for any given locale); otherwise, the argument is returned unchanged.

Notes

Even though islower() can return true for some characters, toupper() may return that lowercase character unchanged as there are no corresponding uppercase characters in the locale.

4.6.3.2.2. toupper_l()

Description

Convert lowercase character to uppercase, per locale (POSIX.1).

Prototype

int toupper_l(int c, locale_t loc);

Parameters

Parameter	Description
c	Character to convert.
loc	Locale used to convert c.

Return value

Converted character.

Additional information

Converts a lowercase letter to a corresponding uppercase letter in locale loc. If the argument c is a character for which islower_l() is true in locale loc, tolower_l() returns the corresponding uppercase letter; otherwise, the argument is returned unchanged.

Notes

Conforms to POSIX.1-2017.

4.6.3.2.3. tolower()

Description

Convert uppercase character to lowercase.

Prototype

int tolower(int c);

Parameters

Parameter	Description
c	Character to convert.

Return value

Converted character.

Additional information

Converts an uppercase letter to a corresponding lowercase letter.

If the argument c is a character for which isupper() is true and there are one or more corresponding characters, as specified by the current locale, for which islower() is true, the tolower() function returns one of the corresponding characters (always the same one for any given locale); otherwise, the argument is returned unchanged.

Notes

Even though isupper() can return true for some characters, tolower() may return that uppercase character unchanged as there are no corresponding lowercase characters in the locale.

4.6.3.2.4. tolower_l()

Description

Convert uppercase character to lowercase, per locale (POSIX.1).

Prototype

int tolower_l(int c, locale_t loc);

Parameters

Parameter	Description
c	Character to convert.
loc	Locale used to convert c.

Return value

Converted character.

Additional information

Converts an uppercase letter to a corresponding lowercase letter in locale loc. If the argument is a character for which isupper_l() is true in locale loc, tolower_l() returns the corresponding lowercase letter; otherwise, the argument is returned unchanged.

Notes

Conforms to POSIX.1-2017.

4.6.4. <errno.h>

4.6.4.1. Errors

4.6.4.1.1. Error names

Description

Symbolic error names for raised errors.

Definition

#define EDOM      0x01
#define EILSEQ    0x02
#define ERANGE    0x03
#define EHEAP     0x04
#define ENOMEM    0x05
#define EINVAL    0x06

Symbols

Definition	Description
EDOM	Domain error
EILSEQ	Illegal multibyte sequence in conversion
ERANGE	Range error
EHEAP	Heap is corrupt
ENOMEM	Out of memory
EINVAL	Invalid parameter

4.6.4.1.2. errno

Description

Macro returning the current error.

Definition

#define errno    (*__SEGGER_RTL_X_errno_addr())

Additional information

The value in errno is significant only when the return value of the call indicated an error. A function that succeeds is allowed to change errno. The value of errno is never set to zero by a library function.

4.6.5. <fenv.h>

4.6.5.1. Floating-point exceptions

Function	Description
feclearexcept()	Clear floating-point exceptions.
feraiseexcept()	Raise floating-point exceptions.
fegetexceptflag()	Get floating-point exceptions.
fesetexceptflag()	Set floating-point exceptions.
fetestexcept()	Test floating-point exceptions.

4.6.5.1.1. feclearexcept()

Description

Clear floating-point exceptions.

Prototype

int feclearexcept(int excepts);

Parameters

Parameter	Description
excepts	Bitmask of floating-point exceptions to clear.

Return value

= 0	Floating-point exceptions successfully cleared.
≠ 0	Floating-point exceptions not cleared or not supported.

Additional information

This function attempts to clear the floating-point exceptions indicated by excepts.

Notes

This function has no return value in ISO C (1999) and an integer return value in ISO C (2008).

4.6.5.1.2. feraiseexcept()

Description

Raise floating-point exceptions.

Prototype

int feraiseexcept(int excepts);

Parameters

Parameter	Description
excepts	Bitmask of floating-point exceptions to raise.

Return value

= 0	All floating-point exceptions successfully raised.
≠ 0	Floating-point exceptions not successuly raised or not supported.

Additional information

This function attempts to raise the floating-point exceptions indicated by excepts.

Notes

This function has no return value in ISO C (1999) and an integer return value in ISO C (2008).

4.6.5.1.3. fegetexceptflag()

Description

Get floating-point exceptions.

Prototype

int fegetexceptflag(fexcept_t * flagp,
                    int         excepts);

Parameters

Parameter	Description
flagp	Pointer to object that receives the floating-point exception state.
excepts	Bitmask of floating-point exceptions to store.

Return value

= 0	Floating-point exceptions correctly stored.
≠ 0	Floating-point exceptions not correctly stored.

Additional information

This function attempts to save the floating-point exceptions indicated by excepts to the object pointed to by flagp.

See also

fesetexceptflag().

4.6.5.1.4. fesetexceptflag()

Description

Set floating-point exceptions.

Prototype

int fesetexceptflag(const fexcept_t * flagp,
                          int         excepts);

Parameters

Parameter	Description
flagp	Pointer to object containing a previously-stored floating-point exception state.
excepts	Bitmask of floating-point exceptions to restore.

Return value

= 0	Floating-point exceptions correctly restored.
≠ 0	Floating-point exceptions not correctly restored.

Additional information

This function attempts to restore the floating-point exceptions indicated by excepts from the object pointed to by flagp. The exceptions to restore as indicated by excepts must have at least been specified when storing the exceptions using fegetexceptflag().

See also

fegetexceptflag().

4.6.5.1.5. fetestexcept()

Description

Test floating-point exceptions.

Prototype

int fetestexcept(int excepts);

Parameters

Parameter	Description
excepts	Bitmask of floating-point exceptions to test.

Return value

The bitmask of all floating-point exceptions that are currently set and are specified in excepts.

Additional information

This function determines which of the floating-point exceptions indicated by excepts are currently set.

4.6.5.2. Floating-point rounding mode

Function	Description
fegetround()	Get floating-point rounding mode.
fesetround()	Set floating-point rounding mode.

4.6.5.2.1. fegetround()

Description

Get floating-point rounding mode.

Prototype

int fegetround(void);

Return value

≥ 0	Current floating-point rounding mode.
< 0	Floating-point rounding mode cannot be determined.

Additional information

This function attempts to read the current floating-point rounding mode.

See also

fesetround().

4.6.5.2.2. fesetround()

Description

Set floating-point rounding mode.

Prototype

int fesetround(int round);

Parameters

Parameter	Description
round	Rounding mode to set.

Return value

= 0	Current floating-point rounding mode is set to round.
≠ 0	Requested floating-point rounding mode cannot be set.

Additional information

This function attempts to set the current floating-point rounding mode to round.

See also

fegetround().

4.6.5.3. Floating-point environment

Function	Description
fegetenv()	Get floating-point environment.
fesetenv()	Set floating-point environment.
feupdateenv()	Restore floating-point environment and reraise exceptions.
feholdexcept()	Save floating-point environment and set non-stop mode.

4.6.5.3.1. fegetenv()

Description

Get floating-point environment.

Prototype

int fegetenv(fenv_t * envp);

Parameters

Parameter	Description
envp	Pointer to object that receives the floating-point environment.

Return value

= 0	Current floating-point environment successfully stored.
≠ 0	Floating-point environment cannot be stored.

Additional information

This function attempts to store the current floating-point environment to the object pointed to by envp.

Notes

This function has no return value in ISO C (1999) and an integer return value in ISO C (2008).

See also

fesetenv().

4.6.5.3.2. fesetenv()

Description

Set floating-point environment.

Prototype

int fesetenv(const fenv_t * envp);

Parameters

Parameter	Description
envp	Pointer to object containing previously-stored floating-point environment.

Return value

= 0	Current floating-point environment successfully restored.
≠ 0	Floating-point environment cannot be restored.

Additional information

This function attempts to restore the floating-point environment from the object pointed to by envp.

Notes

This function has no return value in ISO C (1999) and an integer return value in ISO C (2008).

See also

fegetenv().

4.6.5.3.3. feupdateenv()

Description

Restore floating-point environment and reraise exceptions.

Prototype

int feupdateenv(const fenv_t * envp);

Parameters

Parameter	Description
envp	Pointer to object containing previously-stored floating-point environment.

Return value

= 0	Environment restored and exceptions raised successfully.
≠ 0	Failed to restore environment and raise exceptions.

Additional information

This function attempts to save the currently raised floating-point exceptions, restore the floating-point environment from the object pointed to by envp, and raise the saved exceptions.

Notes

This function has no return value in ISO C (1999) and an integer return value in ISO C (2008).

4.6.5.3.4. feholdexcept()

Description

Save floating-point environment and set non-stop mode.

Prototype

int feholdexcept(fenv_t * envp);

Parameters

Parameter	Description
envp	Pointer to object that receives the floating-point environment.

Return value

= 0	Environment stored and non-stop mode set successfully.
≠ 0	Failed to store environment or set non-stop mode.

Additional information

This function function saves the current floating-point environment to the object pointed to by envp, clears the floating-point status flags, and then installs a non-stop mode for all floating-point exceptions

4.6.6. <float.h>

4.6.6.1. Floating-point constants

4.6.6.1.1. Common parameters

Description

Applies to single-precision and double-precision formats.

Definition

#define FLT_ROUNDS         1
#define FLT_EVAL_METHOD    0
#define FLT_RADIX          2
#define DECIMAL_DIG        17

Symbols

Definition	Description
FLT_ROUNDS	Rounding mode of floating-point addition is round to nearest.
FLT_EVAL_METHOD	All operations and constants are evaluated to the range and precision of the type.
FLT_RADIX	Radix of the exponent representation.
DECIMAL_DIG	Number of decimal digits that can be rounded to a floating-point number without change to the value.

4.6.6.1.2. Float parameters

Description

IEEE 32-bit single-precision floating format parameters.

Definition

#define FLT_MANT_DIG      24
#define FLT_EPSILON       1.19209290E-07f
#define FLT_DIG           6
#define FLT_MIN_EXP       -125
#define FLT_MIN           1.17549435E-38f
#define FLT_MIN_10_EXP    -37
#define FLT_MAX_EXP       +128
#define FLT_MAX           3.40282347E+38f
#define FLT_MAX_10_EXP    +38

Symbols

Definition	Description
FLT_MANT_DIG	Number of base FLT_RADIX digits in the mantissa part of a float.
FLT_EPSILON	Minimum positive number such that 1.0f + FLT_EPSILON ≠ 1.0f.
FLT_DIG	Number of decimal digits of precision of a float.
FLT_MIN_EXP	Minimum value of base FLT_RADIX in the exponent part of a float.
FLT_MIN	Minimum value of a float.
FLT_MIN_10_EXP	Minimum value in base 10 of the exponent part of a float.
FLT_MAX_EXP	Maximum value of base FLT_RADIX in the exponent part of a float.
FLT_MAX	Maximum value of a float.
FLT_MAX_10_EXP	Maximum value in base 10 of the exponent part of a float.

4.6.6.1.3. Double parameters

Description

IEEE 64-bit double-precision floating format parameters.

Definition

#define DBL_MANT_DIG      53
#define DBL_EPSILON       2.2204460492503131E-16
#define DBL_DIG           15
#define DBL_MIN_EXP       -1021
#define DBL_MIN           2.2250738585072014E-308
#define DBL_MIN_10_EXP    -307
#define DBL_MAX_EXP       +1024
#define DBL_MAX           1.7976931348623157E+308
#define DBL_MAX_10_EXP    +308

Symbols

Definition	Description
DBL_MANT_DIG	Number of base DBL_RADIX digits in the mantissa part of a double.
DBL_EPSILON	Minimum positive number such that 1.0 + DBL_EPSILON ≠ 1.0.
DBL_DIG	Number of decimal digits of precision of a double.
DBL_MIN_EXP	Minimum value of base DBL_RADIX in the exponent part of a double.
DBL_MIN	Minimum value of a double.
DBL_MIN_10_EXP	Minimum value in base 10 of the exponent part of a double.
DBL_MAX_EXP	Maximum value of base DBL_RADIX in the exponent part of a double.
DBL_MAX	Maximum value of a double.
DBL_MAX_10_EXP	Maximum value in base 10 of the exponent part of a double.

4.6.7. <iso646.h>

The header <iso646.h> defines macros that expand to the corresponding tokens to ease writing C programs with keyboards that do not have keys for frequently-used operators.

4.6.7.1. Macros

4.6.7.1.1. Replacement macros

Description

Standard replacement macros.

Definition

#define and       &&
#define and_eq    &=
#define bitand    &
#define bitor     |
#define compl     ~
#define not       !
#define not_eq    !=
#define or        ||
#define or_eq     |=
#define xor       ^
#define xor_eq    ^=

4.6.8. <limits.h>

4.6.8.1. Minima and maxima

4.6.8.1.1. Character minima and maxima

Description

Minimum and maximum values for character types.

Definition

#define CHAR_BIT     8
#define CHAR_MIN     0
#define CHAR_MAX     255
#define SCHAR_MAX    127
#define SCHAR_MIN    (-128)
#define UCHAR_MAX    255

Symbols

Definition	Description
CHAR_BIT	Number of bits for smallest object that is not a bit-field (byte).
CHAR_MIN	Minimum value of a plain character.
CHAR_MAX	Maximum value of a plain character.
SCHAR_MAX	Maximum value of a signed character.
SCHAR_MIN	Minimum value of a signed character.
UCHAR_MAX	Maximum value of an unsigned character.

4.6.8.1.2. Short integer minima and maxima

Description

Minimum and maximum values for short integer types.

Definition

#define SHRT_MIN     (-32767 - 1)
#define SHRT_MAX     32767
#define USHRT_MAX    65535

Symbols

Definition	Description
SHRT_MIN	Minimum value of a short integer.
SHRT_MAX	Maximum value of a short integer.
USHRT_MAX	Maximum value of an unsigned short integer.

4.6.8.1.3. Integer minima and maxima

Description

Minimum and maximum values for integer types.

Definition

#define INT_MIN     (-2147483647 - 1)
#define INT_MAX     2147483647
#define UINT_MAX    4294967295u

Symbols

Definition	Description
INT_MIN	Minimum value of an integer.
INT_MAX	Maximum value of an integer.
UINT_MAX	Maximum value of an unsigned integer.

4.6.8.1.4. Long integer minima and maxima (32-bit)

Description

Minimum and maximum values for long integer types.

Definition

#define LONG_MIN     (-2147483647L - 1)
#define LONG_MAX     2147483647L
#define ULONG_MAX    4294967295uL

Symbols

Definition	Description
LONG_MIN	Maximum value of a long integer.
LONG_MAX	Minimum value of a long integer.
ULONG_MAX	Maximum value of an unsigned long integer.

4.6.8.1.5. Long integer minima and maxima (64-bit)

Description

Minimum and maximum values for long integer types.

Definition

#define LONG_MIN     (-9223372036854775807L - 1)
#define LONG_MAX     9223372036854775807L
#define ULONG_MAX    18446744073709551615uL

Symbols

Definition	Description
LONG_MIN	Minimum value of a long integer.
LONG_MAX	Maximum value of a long integer.
ULONG_MAX	Maximum value of an unsigned long integer.

4.6.8.1.6. Long long integer minima and maxima

Description

Minimum and maximum values for long integer types.

Definition

#define LLONG_MIN     (-9223372036854775807LL - 1)
#define LLONG_MAX     9223372036854775807LL
#define ULLONG_MAX    18446744073709551615uLL

Symbols

Definition	Description
LLONG_MIN	Minimum value of a long long integer.
LLONG_MAX	Maximum value of a long long integer.
ULLONG_MAX	Maximum value of an unsigned long long integer.

4.6.8.1.7. Multibyte characters

Description

Maximum number of bytes in a multi-byte character.

Definition

#define MB_LEN_MAX    4

Symbols

Definition	Description
MB_LEN_MAX	Maximum

Additional information

The maximum number of bytes in a multi-byte character for any supported locale. Unicode (ISO 10646) characters between 0x000000 and 0x10FFFF inclusive are supported which convert to a maximum of four bytes in the UTF-8 encoding.

4.6.9. <locale.h>

4.6.9.1. Data types

4.6.9.1.1. __SEGGER_RTL_lconv

Type definition

typedef struct {
  char * decimal_point;
  char * thousands_sep;
  char * grouping;
  char * int_curr_symbol;
  char * currency_symbol;
  char * mon_decimal_point;
  char * mon_thousands_sep;
  char * mon_grouping;
  char * positive_sign;
  char * negative_sign;
  char   int_frac_digits;
  char   frac_digits;
  char   p_cs_precedes;
  char   p_sep_by_space;
  char   n_cs_precedes;
  char   n_sep_by_space;
  char   p_sign_posn;
  char   n_sign_posn;
  char   int_p_cs_precedes;
  char   int_n_cs_precedes;
  char   int_p_sep_by_space;
  char   int_n_sep_by_space;
  char   int_p_sign_posn;
  char   int_n_sign_posn;
} __SEGGER_RTL_lconv;

Structure members

Member	Description
decimal_point	Decimal point separator.
thousands_sep	Separators used to delimit groups of digits to the left of the decimal point for non-monetary quantities.
grouping	Specifies the amount of digits that form each of the groups to be separated by thousands_sep separator for non-monetary quantities.
int_curr_symbol	International currency symbol.
currency_symbol	Local currency symbol.
mon_decimal_point	Decimal-point separator used for monetary quantities.
mon_thousands_sep	Separators used to delimit groups of digits to the left of the decimal point for monetary quantities.
mon_grouping	Specifies the amount of digits that form each of the groups to be separated by mon_thousands_sep separator for monetary quantities.
positive_sign	Sign to be used for nonnegative (positive or zero) monetary quantities.
negative_sign	Sign to be used for negative monetary quantities.
int_frac_digits	Amount of fractional digits to the right of the decimal point for monetary quantities in the international format.
frac_digits	Amount of fractional digits to the right of the decimal point for monetary quantities in the local format.
p_cs_precedes	Whether the currency symbol should precede nonnegative (positive or zero) monetary quantities.
p_sep_by_space	Whether a space should appear between the currency symbol and nonnegative (positive or zero) monetary quantities.
n_cs_precedes	Whether the currency symbol should precede negative monetary quantities.
n_sep_by_space	Whether a space should appear between the currency symbol and negative monetary quantities.
p_sign_posn	Position of the sign for nonnegative (positive or zero) monetary quantities.
n_sign_posn	Position of the sign for negative monetary quantities.
int_p_cs_precedes	Whether int_curr_symbol precedes or succeeds the value for a nonnegative internationally formatted monetary quantity.
int_n_cs_precedes	Whether int_curr_symbol precedes or succeeds the value for a negative internationally formatted monetary quantity.
int_p_sep_by_space	Value indicating the separation of the int_curr_symbol, the sign string, and the value for a nonnegative internationally formatted monetary quantity.
int_n_sep_by_space	Value indicating the separation of the int_curr_symbol, the sign string, and the value for a negative internationally formatted monetary quantity.
int_p_sign_posn	Value indicating the positioning of the positive_sign for a nonnegative internationally formatted monetary quantity.
int_n_sign_posn	Value indicating the positioning of the positive_sign for a negative internationally formatted monetary quantity.

4.6.9.2. Locale management

Function	Description
setlocale()	Set locale.
localeconv()	Get current locale data.

4.6.9.2.1. setlocale()

Description

Set locale.

Prototype

char *setlocale(      int    category,
                const char * loc);

Parameters

Parameter	Description
category	Category of locale to set, see below.
loc	Pointer to name of locale to set or, if NULL, the current locale.

Return value

Returns the name of the current locale.

Additional information

The category parameter can have the following values:

Value	Description
LC_ALL	Entire locale.
LC_COLLATE	Affects strcoll() and strxfrm().
LC_CTYPE	Affects character handling.
LC_MONETARY	Affects monetary formatting information.
LC_NUMERIC	Affects decimal-point character in I/O and string formatting operations.
LC_TIME	Affects strftime().

4.6.9.2.2. localeconv()

Description

Get current locale data.

Prototype

localeconv(void);

Return value

Returns a pointer to a structure of type lconv with the corresponding values for the current locale filled in.

4.6.10. <math.h>

4.6.10.1. Exponential and logarithm functions

Function	Description
sqrt()	Compute square root, double.
sqrtf()	Compute square root, float.
sqrtl()	Compute square root, long double.
cbrt()	Compute cube root, double.
cbrtf()	Compute cube root, float.
cbrtl()	Compute cube root, long double.
rsqrt()	Compute reciprocal square root, double.
rsqrtf()	Compute reciprocal square root, float.
rsqrtl()	Compute reciprocal square root, long double.
exp()	Compute base-e exponential, double.
expf()	Compute base-e exponential, float.
expl()	Compute base-e exponential, long double.
expm1()	Compute base-e exponential, modified, double.
expm1f()	Compute base-e exponential, modified, float.
expm1l()	Compute base-e exponential, modified, long double.
exp2()	Compute base-2 exponential, double.
exp2f()	Compute base-2 exponential, float.
exp2l()	Compute base-2 exponential, long double.
exp10()	Compute base-10 exponential, double.
exp10f()	Compute base-10 exponential, float.
exp10l()	Compute base-10 exponential, long double.
frexp()	Split to significand and exponent, double.
frexpf()	Split to significand and exponent, float.
frexpl()	Split to significand and exponent, long double.
hypot()	Compute magnitude of complex, double.
hypotf()	Compute magnitude of complex, float.
hypotl()	Compute magnitude of complex, long double.
log()	Compute natural logarithm, double.
logf()	Compute natural logarithm, float.
logl()	Compute natural logarithm, long double.
log2()	Compute base-2 logarithm, double.
log2f()	Compute base-2 logarithm, float.
log2l()	Compute base-2 logarithm, long double.
log10()	Compute common logarithm, double.
log10f()	Compute common logarithm, float.
log10l()	Compute common logarithm, long double.
logb()	Radix-indpendent exponent, double.
logbf()	Radix-indpendent exponent, float.
logbl()	Radix-indpendent exponent, long double.
ilogb()	Radix-independent exponent, double.
ilogbf()	Radix-independent exponent, float.
ilogbl()	Radix-independent exponent, long double.
log1p()	Compute natural logarithm plus one, double.
log1pf()	Compute natural logarithm plus one, float.
log1pl()	Compute natural logarithm plus one, long double.
ldexp()	Scale by power of two, double.
ldexpf()	Scale by power of two, float.
ldexpl()	Scale by power of two, long double.
pow()	Raise to power, double.
powf()	Raise to power, float.
powl()	Raise to power, long double.
scalbn()	Scale, double.
scalbnf()	Scale, float.
scalbnl()	Scale, long double.
scalbln()	Scale, double.
scalblnf()	Scale, float.
scalblnl()	Scale, long double.

4.6.10.1.1. sqrt()

Description

Compute square root, double.

Prototype

double sqrt(double x);

Parameters

Parameter	Description
x	Value to compute square root of.

Return value

If x is zero, return x.
If x is infinite, return x.
If x is NaN, return x.
If x < 0, return NaN.
Else, return square root of x.

Additional information

sqrt() computes the nonnegative square root of x. C90 and C99 require that a domain error occurs if the argument is less than zero, sqrt() deviates and always uses IEC 60559 semantics.

4.6.10.1.2. sqrtf()

Description

Compute square root, float.

Prototype

float sqrtf(float x);

Parameters

Parameter	Description
x	Value to compute square root of.

Return value

If x is zero, return x.
If x is infinite, return x.
If x is NaN, return x.
If x < 0, return NaN.
Else, return square root of x.

Additional information

sqrt() computes the nonnegative square root of x. C90 and C99 require that a domain error occurs if the argument is less than zero, sqrt() deviates and always uses IEC 60559 semantics.

4.6.10.1.3. sqrtl()

Description

Compute square root, long double.

Prototype

long double sqrtl(long double x);

Parameters

Parameter	Description
x	Value to compute square root of.

Return value

If x is zero, return x.
If x is infinite, return x.
If x is NaN, return x.
If x < 0, return NaN.
Else, return square root of x.

Additional information

sqrtl() computes the nonnegative square root of x. C90 and C99 require that a domain error occurs if the argument is less than zero, sqrtl() deviates and always uses IEC 60559 semantics.

4.6.10.1.4. cbrt()

Description

Compute cube root, double.

Prototype

double cbrt(double x);

Parameters

Parameter	Description
x	Value to compute cube root of.

Return value

If x is zero, return x.
If x is infinite, return x.
If x is NaN, return x.
Else, return cube root of x.

4.6.10.1.5. cbrtf()

Description

Compute cube root, float.

Prototype

float cbrtf(float x);

Parameters

Parameter	Description
x	Value to compute cube root of.

Return value

If x is zero, return x.
If x is infinite, return x.
If x is NaN, return x.
Else, return cube root of x.

4.6.10.1.6. cbrtl()

Description

Compute cube root, long double.

Prototype

long double cbrtl(long double x);

Parameters

Parameter	Description
x	Value to compute cube root of.

Return value

If x is zero, return x.
If x is infinite, return x.
If x is NaN, return x.
Else, return cube root of x.

4.6.10.1.7. rsqrt()

Description

Compute reciprocal square root, double.

Prototype

double rsqrt(double x);

Parameters

Parameter	Description
x	Value to compute reciprocal square root of.

Return value

If x is +/-zero, return +/-infinity.
If x is positively infinite, return 0.
If x is NaN, return x.
If x < 0, return NaN.
Else, return reciprocal square root of x.

4.6.10.1.8. rsqrtf()

Description

Compute reciprocal square root, float.

Prototype

float rsqrtf(float x);

Parameters

Parameter	Description
x	Value to compute reciprocal square root of.

Return value

If x is +/-zero, return +/-infinity.
If x is positively infinite, return 0.
If x is NaN, return x.
If x < 0, return NaN.
Else, return reciprocal square root of x.

4.6.10.1.9. rsqrtl()

Description

Compute reciprocal square root, long double.

Prototype

long double rsqrtl(long double x);

Parameters

Parameter	Description
x	Value to compute reciprocal square root of.

Return value

If x is +/-zero, return +/-infinity.
If x is positively infinite, return 0.
If x is NaN, return x.
If x < 0, return NaN.
Else, return reciprocal square root of x.

4.6.10.1.10. exp()

Description

Compute base-e exponential, double.

Prototype

double exp(double x);

Parameters

Parameter	Description
x	Value to compute base-e exponential of.

Return value

If x is NaN, return x.
If x is positively infinite, return x.
If x is negatively infinite, return 0.
Else, return base-e exponential of x.

4.6.10.1.11. expf()

Description

Compute base-e exponential, float.

Prototype

float expf(float x);

Parameters

Parameter	Description
x	Value to compute base-e exponential of.

Return value

If x is NaN, return x.
If x is positively infinite, return x.
If x is negatively infinite, return 0.
Else, return base-e exponential of x.

4.6.10.1.12. expl()

Description

Compute base-e exponential, long double.

Prototype

long double expl(long double x);

Parameters

Parameter	Description
x	Value to compute base-e exponential of.

Return value

If x is NaN, return x.
If x is positively infinite, return x.
If x is negatively infinite, return 0.
Else, return base-e exponential of x.

4.6.10.1.13. expm1()

Description

Compute base-e exponential, modified, double.

Prototype

double expm1(double x);

Parameters

Parameter	Description
x	Value to compute exponential of.

Return value

If x is NaN, return x.
Else, return base-e exponential of x minus 1 (e**x - 1).

4.6.10.1.14. expm1f()

Description

Compute base-e exponential, modified, float.

Prototype

float expm1f(float x);

Parameters

Parameter	Description
x	Value to compute exponential of.

Return value

If x is NaN, return x.
Else, return base-e exponential of x minus 1 (e**x - 1).

4.6.10.1.15. expm1l()

Description

Compute base-e exponential, modified, long double.

Prototype

long double expm1l(long double x);

Parameters

Parameter	Description
x	Value to compute exponential of.

Return value

If x is NaN, return x.
Else, return base-e exponential of x minus 1 (e**x - 1).

4.6.10.1.16. exp2()

Description

Compute base-2 exponential, double.

Prototype

double exp2(double x);

Parameters

Parameter	Description
x	Value to compute base-2 exponential of.

Return value

If x is NaN, return x.
If x is positively infinite, return x.
If x is negatively infinite, return 0.
Else, return base-e exponential of x.

4.6.10.1.17. exp2f()

Description

Compute base-2 exponential, float.

Prototype

float exp2f(float x);

Parameters

Parameter	Description
x	Value to compute base-e exponential of.

Return value

If x is NaN, return x.
If x is positively infinite, return x.
If x is negatively infinite, return 0.
Else, return base-e exponential of x.

4.6.10.1.18. exp2l()

Description

Compute base-2 exponential, long double.

Prototype

long double exp2l(long double x);

Parameters

Parameter	Description
x	Value to compute base-2 exponential of.

Return value

If x is NaN, return x.
If x is positively infinite, return x.
If x is negatively infinite, return 0.
Else, return base-e exponential of x.

4.6.10.1.19. exp10()

Description

Compute base-10 exponential, double.

Prototype

double exp10(double x);

Parameters

Parameter	Description
x	Value to compute base-e exponential of.

Return value

If x is NaN, return x.
If x is positively infinite, return x.
If x is negatively infinite, return 0.
Else, return base-e exponential of x.

4.6.10.1.20. exp10f()

Description

Compute base-10 exponential, float.

Prototype

float exp10f(float x);

Parameters

Parameter	Description
x	Value to compute base-e exponential of.

Return value

If x is NaN, return x.
If x is positively infinite, return x.
If x is negatively infinite, return 0.
Else, return base-e exponential of x.

4.6.10.1.21. exp10l()

Description

Compute base-10 exponential, long double.

Prototype

long double exp10l(long double x);

Parameters

Parameter	Description
x	Value to compute base-e exponential of.

Return value

If x is NaN, return x.
If x is positively infinite, return x.
If x is negatively infinite, return 0.
Else, return base-e exponential of x.

4.6.10.1.22. frexp()

Description

Split to significand and exponent, double.

Prototype

double frexp(double   x,
             int    * exp);

Parameters

Parameter	Description
x	Floating value to operate on.
exp	Pointer to integer receiving the power-of-two exponent of x.

Return value

If x is zero, infinite or NaN, return x and store zero into the integer pointed to by exp.
Else, return the value f, such that f has a magnitude in the interval [0.5, 1) and x equals f * pow(2, *exp)

Additional information

Breaks a floating-point number into a normalized fraction and an integral power of two.

4.6.10.1.23. frexpf()

Description

Split to significand and exponent, float.

Prototype

float frexpf(float   x,
             int   * exp);

Parameters

Parameter	Description
x	Floating value to operate on.
exp	Pointer to integer receiving the power-of-two exponent of x.

Return value

If x is zero, infinite or NaN, return x and store zero into the integer pointed to by exp.
Else, return the value f, such that f has a magnitude in the interval [0.5, 1) and x equals f * pow(2, *exp)

Additional information

Breaks a floating-point number into a normalized fraction and an integral power of two.

4.6.10.1.24. frexpl()

Description

Split to significand and exponent, long double.

Prototype

long double frexpl(long double   x,
                   int         * exp);

Parameters

Parameter	Description
x	Floating value to operate on.
exp	Pointer to integer receiving the power-of-two exponent of x.

Return value

If x is zero, infinite or NaN, return x and store zero into the integer pointed to by exp.
Else, return the value f, such that f has a magnitude in the interval [0.5, 1) and x equals f * pow(2, *exp)

Additional information

Breaks a floating-point number into a normalized fraction and an integral power of two.

4.6.10.1.25. hypot()

Description

Compute magnitude of complex, double.

Prototype

double hypot(double x,
             double y);

Parameters

Parameter	Description
x	Value #1.
y	Value #2.

Return value

If x or y are infinite, return infinity.
If x or y is NaN, return NaN.
Else, return sqrt(x*x + y*y).

Additional information

Computes the square root of the sum of the squares of x and y without undue overflow or underflow. If x and y are the lengths of the sides of a right-angled triangle, then this computes the length of the hypotenuse.

4.6.10.1.26. hypotf()

Description

Compute magnitude of complex, float.

Prototype

float hypotf(float x,
             float y);

Parameters

Parameter	Description
x	Value #1.
y	Value #2.

Return value

If x or y are infinite, return infinity.
If x or y is NaN, return NaN.
Else, return sqrt(x*x + y*y).

Additional information

Computes the square root of the sum of the squares of x and y without undue overflow or underflow. If x and y are the lengths of the sides of a right-angled triangle, then this computes the length of the hypotenuse.

4.6.10.1.27. hypotl()

Description

Compute magnitude of complex, long double.

Prototype

long double hypotl(long double x,
                   long double y);

Parameters

Parameter	Description
x	Value #1.
y	Value #2.

Return value

If x or y are infinite, return infinity.
If x or y is NaN, return NaN.
Else, return sqrtl(x*x + y*y).

Additional information

Computes the square root of the sum of the squares of x and y without undue overflow or underflow. If x and y are the lengths of the sides of a right-angled triangle, then this computes the length of the hypotenuse.

4.6.10.1.28. log()

Description

Compute natural logarithm, double.

Prototype

double log(double x);

Parameters

Parameter	Description
x	Value to compute logarithm of.

Return value

If x = NaN, return x.
If x < 0, return NaN.
If x = 0, return -∞.
If x is +∞, return +∞.
ELse, return base-e logarithm of x.

4.6.10.1.29. logf()

Description

Compute natural logarithm, float.

Prototype

float logf(float x);

Parameters

Parameter	Description
x	Value to compute logarithm of.

Return value

If x = NaN, return x.
If x < 0, return NaN.
If x = 0, return negative infinity.
If x is positively infinite, return infinity.
ELse, return base-e logarithm of x.

4.6.10.1.30. logl()

Description

Compute natural logarithm, long double.

Prototype

long double logl(long double x);

Parameters

Parameter	Description
x	Value to compute logarithm of.

Return value

If x = NaN, return x.
If x < 0, return NaN.
If x = 0, return -∞.
If x is +∞, return +∞.
ELse, return base-e logarithm of x.

4.6.10.1.31. log2()

Description

Compute base-2 logarithm, double.

Prototype

double log2(double x);

Parameters

Parameter	Description
x	Value to compute logarithm of.

Return value

If x = NaN, return x.
If x < 0, return NaN.
If x = 0, return negative infinity.
If x is positively infinite, return infinity.
ELse, return base-10 logarithm of x.

4.6.10.1.32. log2f()

Description

Compute base-2 logarithm, float.

Prototype

float log2f(float x);

Parameters

Parameter	Description
x	Value to compute logarithm of.

Return value

If x = NaN, return x.
If x < 0, return NaN.
If x = 0, return negative infinity.
If x is positively infinite, return infinity.
ELse, return base-10 logarithm of x.

4.6.10.1.33. log2l()

Description

Compute base-2 logarithm, long double.

Prototype

long double log2l(long double x);

Parameters

Parameter	Description
x	Value to compute logarithm of.

Return value

If x = NaN, return x.
If x < 0, return NaN.
If x = 0, return negative infinity.
If x is positively infinite, return infinity.
ELse, return base-10 logarithm of x.

4.6.10.1.34. log10()

Description

Compute common logarithm, double.

Prototype

double log10(double x);

Parameters

Parameter	Description
x	Value to compute logarithm of.

Return value

If x = NaN, return x.
If x < 0, return NaN.
If x = 0, return negative infinity.
If x is positively infinite, return infinity.
ELse, return base-10 logarithm of x.

4.6.10.1.35. log10f()

Description

Compute common logarithm, float.

Prototype

float log10f(float x);

Parameters

Parameter	Description
x	Value to compute logarithm of.

Return value

If x = NaN, return x.
If x < 0, return NaN.
If x = 0, return negative infinity.
If x is positively infinite, return infinity.
ELse, return base-10 logarithm of x.

4.6.10.1.36. log10l()

Description

Compute common logarithm, long double.

Prototype

long double log10l(long double x);

Parameters

Parameter	Description
x	Value to compute logarithm of.

Return value

If x = NaN, return x.
If x < 0, return NaN.
If x = 0, return negative infinity.
If x is positively infinite, return infinity.
ELse, return base-10 logarithm of x.

4.6.10.1.37. logb()

Description

Radix-indpendent exponent, double.

Prototype

double logb(double x);

Parameters

Parameter	Description
x	Floating value to operate on.

Return value

If x is zero, return -∞.
If x is infinite, return +∞.
If x is NaN, return NaN.
Else, return integer part of log_FLTRADIX(x).

Additional information

Calculates the exponent of x, which is the integral part of the FLTRADIX-logarithm of x.

4.6.10.1.38. logbf()

Description

Radix-indpendent exponent, float.

Prototype

float logbf(float x);

Parameters

Parameter	Description
x	Floating value to operate on.

Return value

If x is zero, return -∞.
If x is infinite, return +∞.
If x is NaN, return NaN.
Else, return integer part of log_FLTRADIX(x).

Additional information

Calculates the exponent of x, which is the integral part of the FLTRADIX-logarithm of x.

4.6.10.1.39. logbl()

Description

Radix-indpendent exponent, long double.

Prototype

long double logbl(long double x);

Parameters

Parameter	Description
x	Floating value to operate on.

Return value

If x is zero, return -∞.
If x is infinite, return +∞.
If x is NaN, return NaN.
Else, return integer part of log_FLTRADIX(x).

Additional information

Calculates the exponent of x, which is the integral part of the FLTRADIX-logarithm of x.

4.6.10.1.40. ilogb()

Description

Radix-independent exponent, double.

Prototype

int ilogb(double x);

Parameters

Parameter	Description
x	Floating value to operate on.

Return value

If x is zero, return FP_ILOGB0.
If x is NaN, return FP_ILOGBNAN.
If x is infinite, return MAX_INT.
Else, return integer part of log_FLTRADIX(x).

4.6.10.1.41. ilogbf()

Description

Radix-independent exponent, float.

Prototype

int ilogbf(float x);

Parameters

Parameter	Description
x	Floating value to operate on.

Return value

If x is zero, return FP_ILOGB0.
If x is NaN, return FP_ILOGBNAN.
If x is infinite, return MAX_INT.
Else, return integer part of log_FLTRADIX(x).

4.6.10.1.42. ilogbl()

Description

Radix-independent exponent, long double.

Prototype

int ilogbl(long double x);

Parameters

Parameter	Description
x	Floating value to operate on.

Return value

If x is zero, return FP_ILOGB0.
If x is NaN, return FP_ILOGBNAN.
If x is infinite, return MAX_INT.
Else, return integer part of log_FLTRADIX(x).

4.6.10.1.43. log1p()

Description

Compute natural logarithm plus one, double.

Prototype

double log1p(double x);

Parameters

Parameter	Description
x	Value to compute logarithm of.

Return value

If x = NaN, return x.
If x < 0, return NaN.
If x = 0, return negative infinity.
If x is positively infinite, return infinity.
ELse, return base-e logarithm of x+1.

4.6.10.1.44. log1pf()

Description

Compute natural logarithm plus one, float.

Prototype

float log1pf(float x);

Parameters

Parameter	Description
x	Value to compute logarithm of.

Return value

If x = NaN, return x.
If x < 0, return NaN.
If x = 0, return negative infinity.
If x is positively infinite, return infinity.
ELse, return base-e logarithm of x+1.

4.6.10.1.45. log1pl()

Description

Compute natural logarithm plus one, long double.

Prototype

long double log1pl(long double x);

Parameters

Parameter	Description
x	Value to compute logarithm of.

Return value

If x = NaN, return x.
If x < 0, return NaN.
If x = 0, return negative infinity.
If x is positively infinite, return infinity.
ELse, return base-e logarithm of x+1.

4.6.10.1.46. ldexp()

Description

Scale by power of two, double.

Prototype

double ldexp(double x,
             int    n);

Parameters

Parameter	Description
x	Value to scale.
n	Power of two to scale by.

Return value

If x is ±0, return x;
If x is ±∞, return x.
If x is NaN, return x.
Else, return x * 2 ^ n.

Additional information

Multiplies a floating-point number by an integral power of two.

See also

scalbn()

4.6.10.1.47. ldexpf()

Description

Scale by power of two, float.

Prototype

float ldexpf(float x,
             int   n);

Parameters

Parameter	Description
x	Value to scale.
n	Power of two to scale by.

Return value

If x is zero, return x;
If x is infinite, return x.
If x is NaN, return x.
Else, return x * 2^n.

Additional information

Multiplies a floating-point number by an integral power of two.

See also

scalbnf()

4.6.10.1.48. ldexpl()

Description

Scale by power of two, long double.

Prototype

long double ldexpl(long double x,
                   int         n);

Parameters

Parameter	Description
x	Value to scale.
n	Power of two to scale by.

Return value

If x is ±0, return x;
If x is ±∞, return x.
If x is NaN, return x.
Else, return x * 2 ^ n.

Additional information

Multiplies a floating-point number by an integral power of two.

See also

scalbn()

4.6.10.1.49. pow()

Description

Raise to power, double.

Prototype

double pow(double x,
           double y);

Parameters

Parameter	Description
x	Base.
y	Power.

Return value

Return x raised to the power y.

4.6.10.1.50. powf()

Description

Raise to power, float.

Prototype

float powf(float x,
           float y);

Parameters

Parameter	Description
x	Base.
y	Power.

Return value

Return x raised to the power y.

4.6.10.1.51. powl()

Description

Raise to power, long double.

Prototype

long double powl(long double x,
                 long double y);

Parameters

Parameter	Description
x	Base.
y	Power.

Return value

Return x raised to the power y.

4.6.10.1.52. scalbn()

Description

Scale, double.

Prototype

double scalbn(double x,
              int    n);

Parameters

Parameter	Description
x	Value to scale.
n	Power of DBL_RADIX to scale by.

Return value

If x is infinite, return x.
If x is NaN, return x.
Else, return x * DBL_RADIX ^ n.

Additional information

Multiplies a floating-point number by an integral power of DBL_RADIX.

As floating-point arithmetic conforms to IEC 60559, DBL_RADIX is 2 and scalbn() is (in this implementation) identical to ldexp().

See also

ldexp()

4.6.10.1.53. scalbnf()

Description

Scale, float.

Prototype

float scalbnf(float x,
              int   n);

Parameters

Parameter	Description
x	Value to scale.
n	Power of FLT_RADIX to scale by.

Return value

If x is infinite, return x.
If x is NaN, return x.
Else, return x * FLT_RADIX ^ n.

Additional information

Multiplies a floating-point number by an integral power of FLT_RADIX.

As floating-point arithmetic conforms to IEC 60559, FLT_RADIX is 2 and scalbnf() is (in this implementation) identical to ldexpf().

See also

ldexpf()

4.6.10.1.54. scalbnl()

Description

Scale, long double.

Prototype

long double scalbnl(long double x,
                    int         n);

Parameters

Parameter	Description
x	Value to scale.
n	Power of LDBL_RADIX to scale by.

Return value

If x is infinite, return x.
If x is NaN, return x.
Else, return x * LDBL_RADIX ^ n.

Additional information

Multiplies a floating-point number by an integral power of LDBL_RADIX.

As floating-point arithmetic conforms to IEC 60559, LDBL_RADIX is 2 and scalbnl() is (in this implementation) identical to ldexpl().

See also

ldexpl()

4.6.10.1.55. scalbln()

Description

Scale, double.

Prototype

double scalbln(double x,
               long   n);

Parameters

Parameter	Description
x	Value to scale.
n	Power of DBL_RADIX to scale by.

Return value

If x is infinite, return x.
If x is NaN, return x.
Else, return x * DBL_RADIX ^ n.

Additional information

Multiplies a floating-point number by an integral power of DBL_RADIX.

As floating-point arithmetic conforms to IEC 60559, DBL_RADIX is 2 and scalbln() is (in this implementation) identical to ldexp().

See also

ldexp()

4.6.10.1.56. scalblnf()

Description

Scale, float.

Prototype

float scalblnf(float x,
               long  n);

Parameters

Parameter	Description
x	Value to scale.
n	Power of FLT_RADIX to scale by.

Return value

If x is infinite, return x.
If x is NaN, return x.
Else, return x * FLT_RADIX ^ n.

Additional information

Multiplies a floating-point number by an integral power of FLT_RADIX.

As floating-point arithmetic conforms to IEC 60559, FLT_RADIX is 2 and scalbnf() is (in this implementation) identical to ldexpf().

4.6.10.1.57. scalblnl()

Description

Scale, long double.

Prototype

long double scalblnl(long double x,
                     long        n);

Parameters

Parameter	Description
x	Value to scale.
n	Power of LDBL_RADIX to scale by.

Return value

If x is infinite, return x.
If x is NaN, return x.
Else, return x * LDBL_RADIX ^ n.

Additional information

Multiplies a floating-point number by an integral power of LDBL_RADIX.

As floating-point arithmetic conforms to IEC 60559, LDBL_RADIX is 2 and scalblnl() is (in this implementation) identical to ldexpl().

See also

ldexpl()

4.6.10.2. Trigonometric functions

Function	Description
sin()	Calculate sine, double.
sinf()	Calculate sine, float.
sinl()	Calculate sine, long double.
cos()	Calculate cosine, double.
cosf()	Calculate cosine, float.
cosl()	Calculate cosine, long double.
tan()	Compute tangent, double.
tanf()	Compute tangent, float.
tanl()	Compute tangent, long double.
sinh()	Compute hyperbolic sine, double.
sinhf()	Compute hyperbolic sine, float.
sinhl()	Compute hyperbolic sine, long double.
cosh()	Compute hyperbolic cosine, double.
coshf()	Compute hyperbolic cosine, float.
coshl()	Compute hyperbolic cosine, long double.
tanh()	Compute hyperbolic tangent, double.
tanhf()	Compute hyperbolic tangent, float.
tanhl()	Compute hyperbolic tangent, long double.

4.6.10.2.1. sin()

Description

Calculate sine, double.

Prototype

double sin(double x);

Parameters

Parameter	Description
x	Angle to compute sine of, radians.

Return value

If x is NaN, return x.
If x is infinite, return NaN.
Else, return circular sine of x.

4.6.10.2.2. sinf()

Description

Calculate sine, float.

Prototype

float sinf(float x);

Parameters

Parameter	Description
x	Angle to compute sine of, radians.

Return value

If x is NaN, return x.
If x is infinite, return NaN.
Else, return circular sine of x.

4.6.10.2.3. sinl()

Description

Calculate sine, long double.

Prototype

long double sinl(long double x);

Parameters

Parameter	Description
x	Angle to compute sine of, radians.

Return value

If x is NaN, return x.
If x is infinite, return NaN.
Else, return circular sine of x.

4.6.10.2.4. cos()

Description

Calculate cosine, double.

Prototype

double cos(double x);

Parameters

Parameter	Description
x	Angle to compute cosine of, radians.

Return value

If x is NaN, return x.
If x is infinite, return NaN.
Else, return circular cosine of x.

4.6.10.2.5. cosf()

Description

Calculate cosine, float.

Prototype

float cosf(float x);

Parameters

Parameter	Description
x	Angle to compute cosine of, radians.

Return value

If x is NaN, return x.
If x is infinite, return NaN.
Else, return circular cosine of x.

4.6.10.2.6. cosl()

Description

Calculate cosine, long double.

Prototype

long double cosl(long double x);

Parameters

Parameter	Description
x	Angle to compute cosine of, radians.

Return value

If x is NaN, return x.
If x is infinite, return NaN.
Else, return circular cosine of x.

4.6.10.2.7. tan()

Description

Compute tangent, double.

Prototype

double tan(double x);

Parameters

Parameter	Description
x	Angle to compute tangent of, radians.

Return value

If x is zero, return x.
If x is infinite, return NaN.
If x is NaN, return x.
Else, return tangent of x.

4.6.10.2.8. tanf()

Description

Compute tangent, float.

Prototype

float tanf(float x);

Parameters

Parameter	Description
x	Angle to compute tangent of, radians.

Return value

If x is zero, return x.
If x is infinite, return NaN.
If x is NaN, return x.
Else, return tangent of x.

4.6.10.2.9. tanl()

Description

Compute tangent, long double.

Prototype

long double tanl(long double x);

Parameters

Parameter	Description
x	Angle to compute tangent of, radians.

Return value

If x is zero, return x.
If x is infinite, return NaN.
If x is NaN, return x.
Else, return tangent of x.

4.6.10.2.10. sinh()

Description

Compute hyperbolic sine, double.

Prototype

double sinh(double x);

Parameters

Parameter	Description
x	Value to compute hyperbolic sine of.

Return value

If x is NaN, return x.
If x is infinite, return x.
Else, return hyperbolic sine of x.

4.6.10.2.11. sinhf()

Description

Compute hyperbolic sine, float.

Prototype

float sinhf(float x);

Parameters

Parameter	Description
x	Value to compute hyperbolic sine of.

Return value

If x is NaN, return x.
If x is infinite, return x.
Else, return hyperbolic sine of x.

4.6.10.2.12. sinhl()

Description

Compute hyperbolic sine, long double.

Prototype

long double sinhl(long double x);

Parameters

Parameter	Description
x	Value to compute hyperbolic sine of.

Return value

If x is NaN, return x.
If x is infinite, return x.
Else, return hyperbolic sine of x.

4.6.10.2.13. cosh()

Description

Compute hyperbolic cosine, double.

Prototype

double cosh(double x);

Parameters

Parameter	Description
x	Value to compute hyperbolic cosine of.

Return value

If x is NaN, return x.
If x is infinite, return +∞.
Else, return hyperbolic cosine of x.

4.6.10.2.14. coshf()

Description

Compute hyperbolic cosine, float.

Prototype

float coshf(float x);

Parameters

Parameter	Description
x	Value to compute hyperbolic cosine of.

Return value

If x is NaN, return x.
If x is infinite, return +∞.
Else, return hyperbolic cosine of x.

4.6.10.2.15. coshl()

Description

Compute hyperbolic cosine, long double.

Prototype

long double coshl(long double x);

Parameters

Parameter	Description
x	Value to compute hyperbolic cosine of.

Return value

If x is NaN, return x.
If x is infinite, return +∞.
Else, return hyperbolic cosine of x.

4.6.10.2.16. tanh()

Description

Compute hyperbolic tangent, double.

Prototype

double tanh(double x);

Parameters

Parameter	Description
x	Value to compute hyperbolic tangent of.

Return value

If x is NaN, return x.
Else, return hyperbolic tangent of x.

4.6.10.2.17. tanhf()

Description

Compute hyperbolic tangent, float.

Prototype

float tanhf(float x);

Parameters

Parameter	Description
x	Value to compute hyperbolic tangent of.

Return value

If x is NaN, return x.
Else, return hyperbolic tangent of x.

4.6.10.2.18. tanhl()

Description

Compute hyperbolic tangent, long double.

Prototype

long double tanhl(long double x);

Parameters

Parameter	Description
x	Value to compute hyperbolic tangent of.

Return value

If x is NaN, return x.
Else, return hyperbolic tangent of x.

4.6.10.3. Inverse trigonometric functions

Function	Description
asin()	Compute inverse sine, double.
asinf()	Compute inverse sine, float.
asinl()	Compute inverse sine, long double.
acos()	Compute inverse cosine, double.
acosf()	Compute inverse cosine, float.
acosl()	Compute inverse cosine, long double.
atan()	Compute inverse tangent, double.
atanf()	Compute inverse tangent, float.
atanl()	Compute inverse tangent, long double.
atan2()	Compute inverse tangent, with quadrant, double.
atan2f()	Compute inverse tangent, with quadrant, float.
atan2l()	Compute inverse tangent, with quadrant, long double.
asinh()	Compute inverse hyperbolic sine, double.
asinhf()	Compute inverse hyperbolic sine, float.
asinhl()	Compute inverse hyperbolic sine, long double.
acosh()	Compute inverse hyperbolic cosine, double.
acoshf()	Compute inverse hyperbolic cosine, float.
acoshl()	Compute inverse hyperbolic cosine, long double.
atanh()	Compute inverse hyperbolic tangent, double.
atanhf()	Compute inverse hyperbolic tangent, float.
atanhl()	Compute inverse hyperbolic tangent, long double.

4.6.10.3.1. asin()

Description

Compute inverse sine, double.

Prototype

double asin(double x);

Parameters

Parameter	Description
x	Value to compute inverse sine of.

Return value

If x is NaN, return x.
If |x| > 1, return NaN.
Else, return inverse circular sine of x.

Additional information

Calculates the principal value, in radians, of the inverse circular sine of x. The principal value lies in the interval [-Pi/2, Pi/2] radians.

4.6.10.3.2. asinf()

Description

Compute inverse sine, float.

Prototype

float asinf(float x);

Parameters

Parameter	Description
x	Value to compute inverse sine of.

Return value

If x is NaN, return x.
If |x| > 1, return NaN.
Else, return inverse circular sine of x.

Additional information

Calculates the principal value, in radians, of the inverse circular sine of x. The principal value lies in the interval [-Pi/2, Pi/2] radians.

4.6.10.3.3. asinl()

Description

Compute inverse sine, long double.

Prototype

long double asinl(long double x);

Parameters

Parameter	Description
x	Value to compute inverse sine of.

Return value

If x is NaN, return x.
If |x| > 1, return NaN.
Else, return inverse circular sine of x.

Additional information

Calculates the principal value, in radians, of the inverse circular sine of x. The principal value lies in the interval [-Pi/2, Pi/2] radians.

4.6.10.3.4. acos()

Description

Compute inverse cosine, double.

Prototype

double acos(double x);

Parameters

Parameter	Description
x	Value to compute inverse cosine of.

Return value

If x is NaN, return x.
If |x| > 1, return NaN.
Else, return inverse circular cosine of x.

Additional information

Calculates the principal value, in radians, of the inverse circular cosine of x. The principal value lies in the interval [0, Pi] radians.

4.6.10.3.5. acosf()

Description

Compute inverse cosine, float.

Prototype

float acosf(float x);

Parameters

Parameter	Description
x	Value to compute inverse cosine of.

Return value

If x is NaN, return x.
If |x| > 1, return NaN.
Else, return inverse circular cosine of x.

Additional information

Calculates the principal value, in radians, of the inverse circular cosine of x. The principal value lies in the interval [0, Pi] radians.

4.6.10.3.6. acosl()

Description

Compute inverse cosine, long double.

Prototype

long double acosl(long double x);

Parameters

Parameter	Description
x	Value to compute inverse cosine of.

Return value

If x is NaN, return x.
If |x| > 1, return NaN.
Else, return inverse circular cosine of x.

Additional information

Calculates the principal value, in radians, of the inverse circular cosine of x. The principal value lies in the interval [0, Pi] radians.

4.6.10.3.7. atan()

Description

Compute inverse tangent, double.

Prototype

double atan(double x);

Parameters

Parameter	Description
x	Value to compute inverse tangent of.

Return value

If x is NaN, return x.
Else, return inverse tangent of x.

Additional information

Calculates the principal value, in radians, of the inverse tangent of x. The principal value lies in the interval [-Pi/2, Pi/2] radians.

4.6.10.3.8. atanf()

Description

Compute inverse tangent, float.

Prototype

float atanf(float x);

Parameters

Parameter	Description
x	Value to compute inverse tangent of.

Return value

If x is NaN, return x.
Else, return inverse tangent of x.

Additional information

Calculates the principal value, in radians, of the inverse tangent of x. The principal value lies in the interval [-Pi/2, Pi/2] radians.

4.6.10.3.9. atanl()

Description

Compute inverse tangent, long double.

Prototype

long double atanl(long double x);

Parameters

Parameter	Description
x	Value to compute inverse tangent of.

Return value

If x is NaN, return x.
Else, return inverse tangent of x.

Additional information

Calculates the principal value, in radians, of the inverse tangent of x. The principal value lies in the interval [-Pi/2, Pi/2] radians.

4.6.10.3.10. atan2()

Description

Compute inverse tangent, with quadrant, double.

Prototype

double atan2(double y,
             double x);

Parameters

Parameter	Description
y	Rise value of angle.
x	Run value of angle.

Return value

Inverse tangent of y/x.

Additional information

This calculates the value, in radians, of the inverse tangent of y divided by x using the signs of x and y to compute the quadrant of the return value. The principal value lies in the interval [-Pi, +Pi] radians.

4.6.10.3.11. atan2f()

Description

Compute inverse tangent, with quadrant, float.

Prototype

float atan2f(float y,
             float x);

Parameters

Parameter	Description
y	Rise value of angle.
x	Run value of angle.

Return value

Inverse tangent of y/x.

Additional information

This calculates the value, in radians, of the inverse tangent of y divided by x using the signs of x and y to compute the quadrant of the return value. The principal value lies in the interval [-Pi, +Pi] radians.

4.6.10.3.12. atan2l()

Description

Compute inverse tangent, with quadrant, long double.

Prototype

long double atan2l(long double y,
                   long double x);

Parameters

Parameter	Description
y	Rise value of angle.
x	Run value of angle.

Return value

Inverse tangent of y/x.

Additional information

This calculates the value, in radians, of the inverse tangent of y divided by x using the signs of x and y to compute the quadrant of the return value. The principal value lies in the interval [-Pi, +Pi] radians.

4.6.10.3.13. asinh()

Description

Compute inverse hyperbolic sine, double.

Prototype

double asinh(double x);

Parameters

Parameter	Description
x	Value to compute inverse hyperbolic sine of.

Return value

If x is infinite, return x.
If x is NaN, return x.
Else, return inverse hyperbolic sine of x.

4.6.10.3.14. asinhf()

Description

Compute inverse hyperbolic sine, float.

Prototype

float asinhf(float x);

Parameters

Parameter	Description
x	Value to compute inverse hyperbolic sine of.

Return value

If x is infinite, return x.
If x is NaN, return x.
Else, return inverse hyperbolic sine of x.

Additional information

Calculates the inverse hyperbolic sine of x.

4.6.10.3.15. asinhl()

Description

Compute inverse hyperbolic sine, long double.

Prototype

long double asinhl(long double x);

Parameters

Parameter	Description
x	Value to compute inverse hyperbolic sine of.

Return value

If x is infinite, return x.
If x is NaN, return x.
Else, return inverse hyperbolic sine of x.

4.6.10.3.16. acosh()

Description

Compute inverse hyperbolic cosine, double.

Prototype

double acosh(double x);

Parameters

Parameter	Description
x	Value to compute inverse hyperbolic cosine of.

Return value

If x < 1, return NaN.
If x is NaN, return x.
Else, return non-negative inverse hyperbolic cosine of x.

4.6.10.3.17. acoshf()

Description

Compute inverse hyperbolic cosine, float.

Prototype

float acoshf(float x);

Parameters

Parameter	Description
x	Value to compute inverse hyperbolic cosine of.

Return value

If x < 1, return NaN.
If x is NaN, return x.
Else, return non-negative inverse hyperbolic cosine of x.

4.6.10.3.18. acoshl()

Description

Compute inverse hyperbolic cosine, long double.

Prototype

long double acoshl(long double x);

Parameters

Parameter	Description
x	Value to compute inverse hyperbolic cosine of.

Return value

If x < 1, return NaN.
If x is NaN, return x.
Else, return non-negative inverse hyperbolic cosine of x.

4.6.10.3.19. atanh()

Description

Compute inverse hyperbolic tangent, double.

Prototype

double atanh(double x);

Parameters

Parameter	Description
x	Value to compute inverse hyperbolic tangent of.

Return value

If x is NaN, return x.
If |x| > 1, return NaN.
If x = +/-1, return +/-infinity.
Else, return non-negative inverse hyperbolic tangent of x.

4.6.10.3.20. atanhf()

Description

Compute inverse hyperbolic tangent, float.

Prototype

float atanhf(float x);

Parameters

Parameter	Description
x	Value to compute inverse hyperbolic tangent of.

Return value

If x is NaN, return x.
If |x| > 1, return NaN.
If x = +/-1, return +/-infinity.
Else, return non-negative inverse hyperbolic tangent of x.

4.6.10.3.21. atanhl()

Description

Compute inverse hyperbolic tangent, long double.

Prototype

long double atanhl(long double x);

Parameters

Parameter	Description
x	Value to compute inverse hyperbolic tangent of.

Return value

If x is NaN, return x.
If |x| > 1, return NaN.
If x = +/-1, return +/-infinity.
Else, return non-negative inverse hyperbolic tangent of x.

4.6.10.4. Special functions

Function	Description
erf()	Error function, double.
erff()	Error function, float.
erfl()	Error function, long double.
erfc()	Complementary error function, double.
erfcf()	Complementary error function, float.
erfcl()	Complementary error function, long double.
lgamma()	Log-Gamma function, double.
lgammaf()	Log-Gamma function, float.
lgammal()	Log-Gamma function, long double.
tgamma()	Gamma function, double.
tgammaf()	Gamma function, float.
tgammal()	Gamma function, long double.

4.6.10.4.1. erf()

Description

Error function, double.

Prototype

double erf(double x);

Parameters

Parameter	Description
x	Argument.

Return value

erf(x).

4.6.10.4.2. erff()

Description

Error function, float.

Prototype

float erff(float x);

Parameters

Parameter	Description
x	Argument.

Return value

erf(x).

4.6.10.4.3. erfl()

Description

Error function, long double.

Prototype

long double erfl(long double x);

Parameters

Parameter	Description
x	Argument.

Return value

erf(x).

4.6.10.4.4. erfc()

Description

Complementary error function, double.

Prototype

double erfc(double x);

Parameters

Parameter	Description
x	Argument.

Return value

erfc(x).

4.6.10.4.5. erfcf()

Description

Complementary error function, float.

Prototype

float erfcf(float x);

Parameters

Parameter	Description
x	Argument.

Return value

erfc(x).

4.6.10.4.6. erfcl()

Description

Complementary error function, long double.

Prototype

long double erfcl(long double x);

Parameters

Parameter	Description
x	Argument.

Return value

erfc(x).

4.6.10.4.7. lgamma()

Description

Log-Gamma function, double.

Prototype

double lgamma(double x);

Parameters

Parameter	Description
x	Argument.

Return value

log(gamma(x)).

4.6.10.4.8. lgammaf()

Description

Log-Gamma function, float.

Prototype

float lgammaf(float x);

Parameters

Parameter	Description
x	Argument.

Return value

log(gamma(x)).

4.6.10.4.9. lgammal()

Description

Log-Gamma function, long double.

Prototype

long double lgammal(long double x);

Parameters

Parameter	Description
x	Argument.

Return value

log(gamma(x)).

4.6.10.4.10. tgamma()

Description

Gamma function, double.

Prototype

double tgamma(double x);

Parameters

Parameter	Description
x	Argument.

Return value

gamma(x).

4.6.10.4.11. tgammaf()

Description

Gamma function, float.

Prototype

float tgammaf(float x);

Parameters

Parameter	Description
x	Argument.

Return value

gamma(x).

4.6.10.4.12. tgammal()

Description

Gamma function, long double.

Prototype

long double tgammal(long double x);

Parameters

Parameter	Description
x	Argument.

Return value

gamma(x).

4.6.10.5. Rounding and remainder functions

Function	Description
ceil()	Compute smallest integer not less than, double.
ceilf()	Compute smallest integer not less than, float.
ceill()	Compute smallest integer not less than, long double.
floor()	Compute largest integer not greater than, double.
floorf()	Compute largest integer not greater than, float.
floorl()	Compute largest integer not greater than, long double.
trunc()	Truncate to integer, double.
truncf()	Truncate to integer, float.
truncl()	Truncate to integer, long double.
rint()	Round to nearest integer, double.
rintf()	Round to nearest integer, float.
rintl()	Round to nearest integer, long double.
lrint()	Round to nearest integer, double.
lrintf()	Round to nearest integer, float.
lrintl()	Round to nearest integer, long double.
llrint()	Round to nearest integer, double.
llrintf()	Round to nearest integer, float.
llrintl()	Round to nearest integer, long double.
round()	Round to nearest integer, double.
roundf()	Round to nearest integer, float.
roundl()	Round to nearest integer, long double.
lround()	Round to nearest integer, double.
lroundf()	Round to nearest integer, float.
lroundl()	Round to nearest integer, long double.
llround()	Round to nearest integer, double.
llroundf()	Round to nearest integer, float.
llroundl()	Round to nearest integer, long double.
nearbyint()	Round to nearest integer, double.
nearbyintf()	Round to nearest integer, float.
nearbyintl()	Round to nearest integer, long double.
fmod()	Compute remainder after division, double.
fmodf()	Compute remainder after division, float.
fmodl()	Compute remainder after division, long double.
modf()	Separate integer and fractional parts, double.
modff()	Separate integer and fractional parts, float.
modfl()	Separate integer and fractional parts, long double.
remainder()	Compute remainder after division, double.
remainderf()	Compute remainder after division, float.
remainderl()	Compute remainder after division, long double.
remquo()	Compute remainder after division, double.
remquof()	Compute remainder after division, float.
remquol()	Compute remainder after division, long double.

4.6.10.5.1. ceil()

Description

Compute smallest integer not less than, double.

Prototype

double ceil(double x);

Parameters

Parameter	Description
x	Value to compute ceiling of.

Return value

If x is zero, return x.
If x is infinite, return x.
If x is NaN, return x.
Else, return the smallest integer value not greater than x.

4.6.10.5.2. ceilf()

Description

Compute smallest integer not less than, float.

Prototype

float ceilf(float x);

Parameters

Parameter	Description
x	Value to compute ceiling of.

Return value

If x is zero, return x.
If x is infinite, return x.
If x is NaN, return x.
Else, return the smallest integer value not greater than x.

4.6.10.5.3. ceill()

Description

Compute smallest integer not less than, long double.

Prototype

long double ceill(long double x);

Parameters

Parameter	Description
x	Value to compute ceiling of.

Return value

If x is zero, return x.
If x is infinite, return x.
If x is NaN, return x.
Else, return the smallest integer value not greater than x.

4.6.10.5.4. floor()

Description

Compute largest integer not greater than, double.

Prototype

double floor(double x);

Parameters

Parameter	Description
x	Value to floor.

Return value

If x is zero, return x.
If x is infinite, return x.
If x is NaN, return x.
Else, return the largest integer value not greater than x.

4.6.10.5.5. floorf()

Description

Compute largest integer not greater than, float.

Prototype

float floorf(float x);

Parameters

Parameter	Description
x	Value to floor.

Return value

If x is zero, return x.
If x is infinite, return x.
If x is NaN, return x.
Else, return the largest integer value not greater than x.

4.6.10.5.6. floorl()

Description

Compute largest integer not greater than, long double.

Prototype

long double floorl(long double x);

Parameters

Parameter	Description
x	Value to floor.

Return value

If x is zero, return x.
If x is infinite, return x.
If x is NaN, return x.
Else, return the largest integer value not greater than x.

4.6.10.5.7. trunc()

Description

Truncate to integer, double.

Prototype

double trunc(double x);

Parameters

Parameter	Description
x	Value to truncate.

Return value

If x is infinite, return x.
If x is NaN, return x.
Else, return x with fractional part removed.

4.6.10.5.8. truncf()

Description

Truncate to integer, float.

Prototype

float truncf(float x);

Parameters

Parameter	Description
x	Value to truncate.

Return value

If x is infinite, return x.
If x is NaN, return x.
Else, return x with fractional part removed.

4.6.10.5.9. truncl()

Description

Truncate to integer, long double.

Prototype

long double truncl(long double x);

Parameters

Parameter	Description
x	Value to truncate.

Return value

If x is infinite, return x.
If x is NaN, return x.
Else, return x with fractional part removed.

4.6.10.5.10. rint()

Description

Round to nearest integer, double.

Prototype

double rint(double x);

Parameters

Parameter	Description
x	Value to compute nearest integer of.

Return value

If x is infinite, return x.
If x is NaN, return x.
Else, return the nearest integer value to x.

4.6.10.5.11. rintf()

Description

Round to nearest integer, float.

Prototype

float rintf(float x);

Parameters

Parameter	Description
x	Value to compute nearest integer of.

Return value

If x is infinite, return x.
If x is NaN, return x.
Else, return the nearest integer value to x.

4.6.10.5.12. rintl()

Description

Round to nearest integer, long double.

Prototype

long double rintl(long double x);

Parameters

Parameter	Description
x	Value to compute nearest integer of.

Return value

If x is infinite, return x.
If x is NaN, return x.
Else, return the nearest integer value to x.

4.6.10.5.13. lrint()

Description

Round to nearest integer, double.

Prototype

long lrint(double x);

Parameters

Parameter	Description
x	Value to compute nearest integer of.

Return value

If x is infinite, return x.
If x is NaN, return x.
Else, return the nearest integer value to x.

4.6.10.5.14. lrintf()

Description

Round to nearest integer, float.

Prototype

long lrintf(float x);

Parameters

Parameter	Description
x	Value to compute nearest integer of.

Return value

If x is infinite, return x.
If x is NaN, return x.
Else, return the nearest integer value to x.

4.6.10.5.15. lrintl()

Description

Round to nearest integer, long double.

Prototype

long lrintl(long double x);

Parameters

Parameter	Description
x	Value to compute nearest integer of.

Return value

If x is infinite, return x.
If x is NaN, return x.
Else, return the nearest integer value to x.

4.6.10.5.16. llrint()

Description

Round to nearest integer, double.

Prototype

long long llrint(double x);

Parameters

Parameter	Description
x	Value to compute nearest integer of.

Return value

If x is infinite, return x.
If x is NaN, return x.
Else, return the nearest integer value to x.

4.6.10.5.17. llrintf()

Description

Round to nearest integer, float.

Prototype

long long llrintf(float x);

Parameters

Parameter	Description
x	Value to compute nearest integer of.

Return value

If x is infinite, return x.
If x is NaN, return x.
Else, return the nearest integer value to x.

4.6.10.5.18. llrintl()

Description

Round to nearest integer, long double.

Prototype

long long llrintl(long double x);

Parameters

Parameter	Description
x	Value to compute nearest integer of.

Return value

If x is infinite, return x.
If x is NaN, return x.
Else, return the nearest integer value to x.

4.6.10.5.19. round()

Description

Round to nearest integer, double.

Prototype

double round(double x);

Parameters

Parameter	Description
x	Value to compute nearest integer of.

Return value

If x is infinite, return x.
If x is NaN, return x.
Else, return the nearest integer value to x, ties away from zero.

4.6.10.5.20. roundf()

Description

Round to nearest integer, float.

Prototype

float roundf(float x);

Parameters

Parameter	Description
x	Value to compute nearest integer of.

Return value

If x is infinite, return x.
If x is NaN, return x.
Else, return the nearest integer value to x, ties away from zero.

4.6.10.5.21. roundl()

Description

Round to nearest integer, long double.

Prototype

long double roundl(long double x);

Parameters

Parameter	Description
x	Value to compute nearest integer of.

Return value

If x is infinite, return x.
If x is NaN, return x.
Else, return the nearest integer value to x, ties away from zero.

4.6.10.5.22. lround()

Description

Round to nearest integer, double.

Prototype

long lround(double x);

Parameters

Parameter	Description
x	Value to compute nearest integer of.

Return value

If x is infinite, return x.
If x is NaN, return x.
Else, return the nearest integer value to x.

4.6.10.5.23. lroundf()

Description

Round to nearest integer, float.

Prototype

long lroundf(float x);

Parameters

Parameter	Description
x	Value to compute nearest integer of.

Return value

If x is infinite, return x.
If x is NaN, return x.
Else, return the nearest integer value to x.

4.6.10.5.24. lroundl()

Description

Round to nearest integer, long double.

Prototype

long lroundl(long double x);

Parameters

Parameter	Description
x	Value to compute nearest integer of.

Return value

If x is infinite, return x.
If x is NaN, return x.
Else, return the nearest integer value to x.

4.6.10.5.25. llround()

Description

Round to nearest integer, double.

Prototype

long long llround(double x);

Parameters

Parameter	Description
x	Value to compute nearest integer of.

Return value

If x is infinite, return x.
If x is NaN, return x.
Else, return the nearest integer value to x.

4.6.10.5.26. llroundf()

Description

Round to nearest integer, float.

Prototype

long long llroundf(float x);

Parameters

Parameter	Description
x	Value to compute nearest integer of.

Return value

If x is infinite, return x.
If x is NaN, return x.
Else, return the nearest integer value to x.

4.6.10.5.27. llroundl()

Description

Round to nearest integer, long double.

Prototype

long long llroundl(long double x);

Parameters

Parameter	Description
x	Value to compute nearest integer of.

Return value

If x is infinite, return x.
If x is NaN, return x.
Else, return the nearest integer value to x.

4.6.10.5.28. nearbyint()

Description

Round to nearest integer, double.

Prototype

double nearbyint(double x);

Parameters

Parameter	Description
x	Value to compute nearest integer of.

Return value

If x is infinite, return x.
If x is NaN, return x.
Else, return the nearest integer value to x.

4.6.10.5.29. nearbyintf()

Description

Round to nearest integer, float.

Prototype

float nearbyintf(float x);

Parameters

Parameter	Description
x	Value to compute nearest integer of.

Return value

If x is infinite, return x.
If x is NaN, return x.
Else, return the nearest integer value to x.

4.6.10.5.30. nearbyintl()

Description

Round to nearest integer, long double.

Prototype

long double nearbyintl(long double x);

Parameters

Parameter	Description
x	Value to compute nearest integer of.

Return value

If x is infinite, return x.
If x is NaN, return x.
Else, return the nearest integer value to x.

4.6.10.5.31. fmod()

Description

Compute remainder after division, double.

Prototype

double fmod(double x,
            double y);

Parameters

Parameter	Description
x	Value #1.
y	Value #2.

Return value

If x is NaN, return NaN.
If x is zero and y is nonzero, return x.
If x is infinite, return NaN.
If x is finite and y is infinite, return x.
If y is NaN, return NaN.
If y is zero, return NaN.
Else, return remainder of x divided by y.

Additional information

Computes the floating-point remainder of x divided by y, i.e. the value x - i*y for some integer i such that, if y is nonzero, the result has the same sign as x and magnitude less than the magnitude of y.

4.6.10.5.32. fmodf()

Description

Compute remainder after division, float.

Prototype

float fmodf(float x,
            float y);

Parameters

Parameter	Description
x	Value #1.
y	Value #2.

Return value

If x is NaN, return NaN.
If x is zero and y is nonzero, return x.
If x is infinite, return NaN.
If x is finite and y is infinite, return x.
If y is NaN, return NaN.
If y is zero, return NaN.
Else, return remainder of x divided by y.

Additional information

Computes the floating-point remainder of x divided by y, i.e. the value x - i*y for some integer i such that, if y is nonzero, the result has the same sign as x and magnitude less than the magnitude of y.

4.6.10.5.33. fmodl()

Description

Compute remainder after division, long double.

Prototype

long double fmodl(long double x,
                  long double y);

Parameters

Parameter	Description
x	Value #1.
y	Value #2.

Return value

If x is NaN, return NaN.
If x is zero and y is nonzero, return x.
If x is infinite, return NaN.
If x is finite and y is infinite, return x.
If y is NaN, return NaN.
If y is zero, return NaN.
Else, return remainder of x divided by y.

Additional information

Computes the floating-point remainder of x divided by y, i.e. the value x - i*y for some integer i such that, if y is nonzero, the result has the same sign as x and magnitude less than the magnitude of y.

4.6.10.5.34. modf()

Description

Separate integer and fractional parts, double.

Prototype

double modf(double   x,
            double * iptr);

Parameters

Parameter	Description
x	Value to separate.
iptr	Pointer to object that receives the integral part of x.

Return value

The signed fractional part of x.

Additional information

Breaks x into integral and fractional parts, each of which has the same type and sign as x.

The integral part (in floating-point format) is stored in the object pointed to by iptr and modf() returns the signed fractional part of x.

4.6.10.5.35. modff()

Description

Separate integer and fractional parts, float.

Prototype

float modff(float   x,
            float * iptr);

Parameters

Parameter	Description
x	Value to separate.
iptr	Pointer to object that receives the integral part of x.

Return value

The signed fractional part of x.

Additional information

Breaks x into integral and fractional parts, each of which has the same type and sign as x.

The integral part (in floating-point format) is stored in the object pointed to by iptr and modff() returns the signed fractional part of x.

4.6.10.5.36. modfl()

Description

Separate integer and fractional parts, long double.

Prototype

long double modfl(long double   x,
                  long double * iptr);

Parameters

Parameter	Description
x	Value to separate.
iptr	Pointer to object that receives the integral part of x.

Return value

The signed fractional part of x.

Additional information

Breaks x into integral and fractional parts, each of which has the same type and sign as x.

The integral part (in floating-point format) is stored in the object pointed to by iptr and modf() returns the signed fractional part of x.

4.6.10.5.37. remainder()

Description

Compute remainder after division, double.

Prototype

double remainder(double x,
                 double y);

Parameters

Parameter	Description
x	Value #1.
y	Value #2.

Return value

If x is NaN, return NaN.
If x is zero and y is nonzero, return x.
If x is infinite, return NaN.
If x is finite and y is infinite, return x.
If y is NaN, return NaN.
If y is zero, return NaN.
Else, return remainder of x divided by y.

Additional information

Computes the floating-point remainder of x divided by y, i.e. the value x - i*y for some integer i such that, if y is nonzero, the result has the same sign as x and magnitude less than the magnitude of y.

4.6.10.5.38. remainderf()

Description

Compute remainder after division, float.

Prototype

float remainderf(float x,
                 float y);

Parameters

Parameter	Description
x	Value #1.
y	Value #2.

Return value

If x is NaN, return NaN.
If x is zero and y is nonzero, return x.
If x is infinite, return NaN.
If x is finite and y is infinite, return x.
If y is NaN, return NaN.
If y is zero, return NaN.
Else, return remainder of x divided by y.

Additional information

Computes the floating-point remainder of x divided by y, i.e. the value x - i*y for some integer i such that, if y is nonzero, the result has the same sign as x and magnitude less than the magnitude of y.

4.6.10.5.39. remainderl()

Description

Compute remainder after division, long double.

Prototype

long double remainderl(long double x,
                       long double y);

Parameters

Parameter	Description
x	Value #1.
y	Value #2.

Return value

If x is NaN, return NaN.
If x is zero and y is nonzero, return x.
If x is infinite, return NaN.
If x is finite and y is infinite, return x.
If y is NaN, return NaN.
If y is zero, return NaN.
Else, return remainder of x divided by y.

Additional information

Computes the floating-point remainder of x divided by y, i.e. the value x - i*y for some integer i such that, if y is nonzero, the result has the same sign as x and magnitude less than the magnitude of y.

4.6.10.5.40. remquo()

Description

Compute remainder after division, double.

Prototype

double remquo(double   x,
              double   y,
              int    * quo);

Parameters

Parameter	Description
x	Value #1.
y	Value #2.
quo	Pointer to object that receives the integer part of x divided by y.

Return value

If x is NaN, return NaN.
If x is zero and y is nonzero, return x.
If x is infinite, return NaN.
If x is finite and y is infinite, return x.
If y is NaN, return NaN.
If y is zero, return NaN.
Else, return remainder of x divided by y.

Additional information

Computes the floating-point remainder of x divided by y, i.e. the value x - i*y for some integer i such that, if y is nonzero, the result has the same sign as x and magnitude less than the magnitude of y.

4.6.10.5.41. remquof()

Description

Compute remainder after division, float.

Prototype

float remquof(float   x,
              float   y,
              int   * quo);

Parameters

Parameter	Description
x	Value #1.
y	Value #2.
quo	Pointer to object that receives the integer part of x divided by y.

Return value

If x is NaN, return NaN.
If x is zero and y is nonzero, return x.
If x is infinite, return NaN.
If x is finite and y is infinite, return x.
If y is NaN, return NaN.
If y is zero, return NaN.
Else, return remainder of x divided by y.

Additional information

Computes the floating-point remainder of x divided by y, i.e. the value x - i*y for some integer i such that, if y is nonzero, the result has the same sign as x and magnitude less than the magnitude of y.

4.6.10.5.42. remquol()

Description

Compute remainder after division, long double.

Prototype

long double remquol(long double   x,
                    long double   y,
                    int         * quo);

Parameters

Parameter	Description
x	Value #1.
y	Value #2.
quo	Pointer to object that receives the integer part of x divided by y.

Return value

If x is NaN, return NaN.
If x is zero and y is nonzero, return x.
If x is infinite, return NaN.
If x is finite and y is infinite, return x.
If y is NaN, return NaN.
If y is zero, return NaN.
Else, return remainder of x divided by y.

Additional information

Computes the floating-point remainder of x divided by y, i.e. the value x - i*y for some integer i such that, if y is nonzero, the result has the same sign as x and magnitude less than the magnitude of y.

4.6.10.6. Absolute value functions

Function	Description
fabs()	Compute absolute value, double.
fabsf()	Compute absolute value, float.
fabsl()	Compute absolute value, long double.

4.6.10.6.1. fabs()

Description

Compute absolute value, double.

Prototype

double fabs(double x);

Parameters

Parameter	Description
x	Value to compute magnitude of.

Return value

If x is NaN, return x.
Else, absolute value of x.

4.6.10.6.2. fabsf()

Description

Compute absolute value, float.

Prototype

float fabsf(float x);

Parameters

Parameter	Description
x	Value to compute magnitude of.

Return value

If x is NaN, return x.
Else, absolute value of x.

4.6.10.6.3. fabsl()

Description

Compute absolute value, long double.

Prototype

long double fabsl(long double x);

Parameters

Parameter	Description
x	Value to compute magnitude of.

Return value

If x is NaN, return x.
Else, absolute value of x.

4.6.10.7. Fused multiply functions

Function	Description
fma()	Compute fused multiply-add, double.
fmaf()	Compute fused multiply-add, float.
fmal()	Compute fused multiply-add, long double.

4.6.10.7.1. fma()

Description

Compute fused multiply-add, double.

Prototype

double fma(double x,
           double y,
           double z);

Parameters

Parameter	Description
x	Multiplicand.
y	Multiplier.
z	Summand.

Return value

Return (x * y) + z.

4.6.10.7.2. fmaf()

Description

Compute fused multiply-add, float.

Prototype

float fmaf(float x,
           float y,
           float z);

Parameters

Parameter	Description
x	Multiplier.
y	Multiplicand.
z	Summand.

Return value

Return (x * y) + z.

4.6.10.7.3. fmal()

Description

Compute fused multiply-add, long double.

Prototype

long double fmal(long double x,
                 long double y,
                 long double z);

Parameters

Parameter	Description
x	Multiplicand.
y	Multiplier.
z	Summand.

Return value

Return (x * y) + z.

4.6.10.8. Maximum, minimum, and positive difference functions

Function	Description
fmin()	Compute minimum, double.
fminf()	Compute minimum, float.
fminl()	Compute minimum, long double.
fmax()	Compute maximum, double.
fmaxf()	Compute maximum, float.
fmaxl()	Compute maximum, long double.
fdim()	Positive difference, double.
fdimf()	Positive difference, float.
fdiml()	Positive difference, long double.

4.6.10.8.1. fmin()

Description

Compute minimum, double.

Prototype

double fmin(double x,
            double y);

Parameters

Parameter	Description
x	Value #1.
y	Value #2.

Return value

If x is NaN, return y.
If y is NaN, return x.
Else, return minimum of x and y.

4.6.10.8.2. fminf()

Description

Compute minimum, float.

Prototype

float fminf(float x,
            float y);

Parameters

Parameter	Description
x	Value #1.
y	Value #2.

Return value

If x is NaN, return y.
If y is NaN, return x.
Else, return minimum of x and y.

4.6.10.8.3. fminl()

Description

Compute minimum, long double.

Prototype

long double fminl(long double x,
                  long double y);

Parameters

Parameter	Description
x	Value #1.
y	Value #2.

Return value

If x is NaN, return y.
If y is NaN, return x.
Else, return minimum of x and y.

4.6.10.8.4. fmax()

Description

Compute maximum, double.

Prototype

double fmax(double x,
            double y);

Parameters

Parameter	Description
x	Value #1.
y	Value #2.

Return value

If x is NaN, return y.
If y is NaN, return x.
Else, return maximum of x and y.

4.6.10.8.5. fmaxf()

Description

Compute maximum, float.

Prototype

float fmaxf(float x,
            float y);

Parameters

Parameter	Description
x	Value #1.
y	Value #2.

Return value

If x is NaN, return y.
If y is NaN, return x.
Else, return maximum of x and y.

4.6.10.8.6. fmaxl()

Description

Compute maximum, long double.

Prototype

long double fmaxl(long double x,
                  long double y);

Parameters

Parameter	Description
x	Value #1.
y	Value #2.

Return value

If x is NaN, return y.
If y is NaN, return x.
Else, return maximum of x and y.

4.6.10.8.7. fdim()

Description

Positive difference, double.

Prototype

double fdim(double x,
            double y);

Parameters

Parameter	Description
x	Value #1.
y	Value #2.

Return value

If x > y, x-y.
Else, +0.

4.6.10.8.8. fdimf()

Description

Positive difference, float.

Prototype

float fdimf(float x,
            float y);

Parameters

Parameter	Description
x	Value #1.
y	Value #2.

Return value

If x > y, x-y.
Else, +0.

4.6.10.8.9. fdiml()

Description

Positive difference, long double.

Prototype

long double fdiml(long double x,
                  long double y);

Parameters

Parameter	Description
x	Value #1.
y	Value #2.

Return value

If x > y, x-y.
Else, +0.

4.6.10.9. Miscellaneous functions

Function	Description
nextafter()	Next machine-floating value, double.
nextafterf()	Next machine-floating value, float.
nextafterl()	Next machine-floating value, long double.
nexttoward()	Next machine-floating value, double.
nexttowardf()	Next machine-floating value, float.
nexttowardl()	Next machine-floating value, long double.
nan()	Parse NaN, double.
nanf()	Parse NaN, float.
nanl()	Parse NaN, long double.
copysign()	Copy sign, double.
copysignf()	Copy sign, float.
copysignl()	Copy sign, long double.

4.6.10.9.1. nextafter()

Description

Next machine-floating value, double.

Prototype

double nextafter(double x,
                 double y);

Parameters

Parameter	Description
x	Value to step from.
y	Director to step in.

Return value

Next machine-floating value after x in direction of y.

4.6.10.9.2. nextafterf()

Description

Next machine-floating value, float.

Prototype

float nextafterf(float x,
                 float y);

Parameters

Parameter	Description
x	Value to step from.
y	Director to step in.

Return value

Next machine-floating value after x in direction of y.

4.6.10.9.3. nextafterl()

Description

Next machine-floating value, long double.

Prototype

long double nextafterl(long double x,
                       long double y);

Parameters

Parameter	Description
x	Value to step from.
y	Director to step in.

Return value

Next machine-floating value after x in direction of y.

4.6.10.9.4. nexttoward()

Description

Next machine-floating value, double.

Prototype

double nexttoward(double      x,
                  long double y);

Parameters

Parameter	Description
x	Value to step from.
y	Direction to step in.

Return value

Next machine-floating value after x in direction of y.

4.6.10.9.5. nexttowardf()

Description

Next machine-floating value, float.

Prototype

float nexttowardf(float       x,
                  long double y);

Parameters

Parameter	Description
x	Value to step from.
y	Direction to step in.

Return value

Next machine-floating value after x in direction of y.

4.6.10.9.6. nexttowardl()

Description

Next machine-floating value, long double.

Prototype

long double nexttowardl(long double x,
                        long double y);

Parameters

Parameter	Description
x	Value to step from.
y	Direction to step in.

Return value

Next machine-floating value after x in direction of y.

4.6.10.9.7. nan()

Description

Parse NaN, double.

Prototype

double nan(const char * tag);

Parameters

Parameter	Description
tag	NaN tag.

Return value

Quiet NaN formed from tag.

4.6.10.9.8. nanf()

Description

Parse NaN, float.

Prototype

float nanf(const char * tag);

Parameters

Parameter	Description
tag	NaN tag.

Return value

Quiet NaN formed from tag.

4.6.10.9.9. nanl()

Description

Parse NaN, long double.

Prototype

long double nanl(const char * tag);

Parameters

Parameter	Description
tag	NaN tag.

Return value

Quiet NaN formed from tag.

4.6.10.9.10. copysign()

Description

Copy sign, double.

Prototype

double copysign(double x,
                double y);

Parameters

Parameter	Description
x	Floating value to inject sign into.
y	Floating value carrying the sign to inject.

Return value

x with the sign of y.

4.6.10.9.11. copysignf()

Description

Copy sign, float.

Prototype

float copysignf(float x,
                float y);

Parameters

Parameter	Description
x	Floating value to inject sign into.
y	Floating value carrying the sign to inject.

Return value

x with the sign of y.

4.6.10.9.12. copysignl()

Description

Copy sign, long double.

Prototype

long double copysignl(long double x,
                      long double y);

Parameters

Parameter	Description
x	Floating value to inject sign into.
y	Floating value carrying the sign to inject.

Return value

x with the sign of y.

4.6.11. <setjmp.h>

4.6.11.1. Non-local flow control

4.6.11.1.1. setjmp()

Description

Save calling environment for non-local jump.

Prototype

int setjmp(jmp_buf buf);

Parameters

Parameter	Description
buf	Buffer to save context into.

Return value

On return from a direct invocation, returns the value zero. On return from a call to the longjmp() function, returns a nonzero value determined by the call to longjmp().

Additional information

Saves its calling environment in env for later use by the longjmp() function.

The environment saved by a call to setjmp () consists of information sufficient for a call to the longjmp() function to return execution to the correct block and invocation of that block, were it called recursively.

4.6.11.1.2. longjmp()

Description

Restores the saved environment.

Prototype

void longjmp(jmp_buf buf,
             int     val);

Parameters

Parameter	Description
buf	Buffer to restore context from.
val	Value to return to setjmp() call.

Additional information

Restores the environment saved by setjmp() in the corresponding env argument. If there has been no such invocation, or if the function containing the invocation of setjmp() has terminated execution in the interim, the behavior of longjmp() is undefined.

After longjmp() is completed, program execution continues as if the corresponding invocation of setjmp() had just returned the value specified by val.

Objects of automatic storage allocation that are local to the function containing the invocation of the corresponding setjmp() that do not have volatile-qualified type and have been changed between the setjmp() invocation and longjmp() call are indeterminate.

Notes

longjmp() cannot cause setjmp() to return the value 0; if val is 0, setjmp() returns the value 1.

4.6.12. <stdbool.h>

4.6.12.1. Macros

4.6.12.1.1. bool

Description

Macros expanding to support the Boolean type.

Definition

#define bool     _Bool
#define true     1
#define false    0

Symbols

Definition	Description
bool	Underlying boolean type
true	Boolean true value
false	Boolean false value

4.6.13. <stddef.h>

4.6.13.1. Macros

4.6.13.1.1. NULL

Description

Null-pointer constant.

Definition

#define NULL    0

Symbols

Definition	Description
NULL	Null pointer

4.6.13.1.2. offsetof

Description

Calculate offset of member from start of structure.

Definition

#define offsetof(s,m)    ((size_t)&(((s *)0)->m))

Symbols

Definition	Description
offsetof(s,m)	Offset of m within s

4.6.13.2. Types

4.6.13.2.1. size_t

Description

Unsigned integral type returned by the sizeof operator.

Type definition

typedef __SEGGER_RTL_SIZE_T size_t;

4.6.13.2.2. ptrdiff_t

Description

Signed integral type of the result of subtracting two pointers.

Type definition

typedef __SEGGER_RTL_PTRDIFF_T ptrdiff_t;

4.6.13.2.3. wchar_t

Description

Integral type that can hold one wide character.

Type definition

typedef __SEGGER_RTL_WCHAR_T wchar_t;

4.6.14. <stdint.h>

4.6.14.1. Minima and maxima

4.6.14.1.1. Signed integer minima and maxima

Description

Minimum and maximum values for signed integer types.

Definition

#define INT8_MIN     (-128)
#define INT8_MAX     127
#define INT16_MIN    (-32767-1)
#define INT16_MAX    32767
#define INT32_MIN    (-2147483647L-1)
#define INT32_MAX    2147483647L
#define INT64_MIN    (-9223372036854775807LL-1)
#define INT64_MAX    9223372036854775807LL

Symbols

Definition	Description
INT8_MIN	Minimum value of int8_t
INT8_MAX	Maximum value of int8_t
INT16_MIN	Minimum value of int16_t
INT16_MAX	Maximum value of int16_t
INT32_MIN	Minimum value of int32_t
INT32_MAX	Maximum value of int32_t
INT64_MIN	Minimum value of int64_t
INT64_MAX	Maximum value of int64_t

4.6.14.1.2. Unsigned integer minima and maxima

Description

Minimum and maximum values for unsigned integer types.

Definition

#define UINT8_MAX     255
#define UINT16_MAX    65535
#define UINT32_MAX    4294967295UL
#define UINT64_MAX    18446744073709551615ULL

Symbols

Definition	Description
UINT8_MAX	Maximum value of uint8_t
UINT16_MAX	Maximum value of uint16_t
UINT32_MAX	Maximum value of uint32_t
UINT64_MAX	Maximum value of uint64_t

4.6.14.1.3. Maximal integer minima and maxima

Description

Minimum and maximum values for signed and unsigned maximal-integer types.

Definition

#define INTMAX_MIN     INT64_MIN
#define INTMAX_MAX     INT64_MAX
#define UINTMAX_MAX    UINT64_MAX

Symbols

Definition	Description
INTMAX_MIN	Minimum value of intmax_t
INTMAX_MAX	Maximum value of intmax_t
UINTMAX_MAX	Maximum value of uintmax_t

4.6.14.1.4. Least integer minima and maxima

Description

Minimum and maximum values for signed and unsigned least-integer types.

Definition

#define INT_LEAST8_MIN      INT8_MIN
#define INT_LEAST8_MAX      INT8_MAX
#define INT_LEAST16_MIN     INT16_MIN
#define INT_LEAST16_MAX     INT16_MAX
#define INT_LEAST32_MIN     INT32_MIN
#define INT_LEAST32_MAX     INT32_MAX
#define INT_LEAST64_MIN     INT64_MIN
#define INT_LEAST64_MAX     INT64_MAX
#define UINT_LEAST8_MAX     UINT8_MAX
#define UINT_LEAST16_MAX    UINT16_MAX
#define UINT_LEAST32_MAX    UINT32_MAX
#define UINT_LEAST64_MAX    UINT64_MAX

Symbols

Definition	Description
INT_LEAST8_MIN	Minimum value of int_least8_t
INT_LEAST8_MAX	Maximum value of int_least8_t
INT_LEAST16_MIN	Minimum value of int_least16_t
INT_LEAST16_MAX	Maximum value of int_least16_t
INT_LEAST32_MIN	Minimum value of int_least32_t
INT_LEAST32_MAX	Maximum value of int_least32_t
INT_LEAST64_MIN	Minimum value of int_least64_t
INT_LEAST64_MAX	Maximum value of int_least64_t
UINT_LEAST8_MAX	Maximum value of uint_least8_t
UINT_LEAST16_MAX	Maximum value of uint_least16_t
UINT_LEAST32_MAX	Maximum value of uint_least32_t
UINT_LEAST64_MAX	Maximum value of uint_least64_t

4.6.14.1.5. Fast integer minima and maxima

Description

Minimum and maximum values for signed and unsigned fast-integer types.

Definition

#define INT_FAST8_MIN      INT8_MIN
#define INT_FAST8_MAX      INT8_MAX
#define INT_FAST16_MIN     INT32_MIN
#define INT_FAST16_MAX     INT32_MAX
#define INT_FAST32_MIN     INT32_MIN
#define INT_FAST32_MAX     INT32_MAX
#define INT_FAST64_MIN     INT64_MIN
#define INT_FAST64_MAX     INT64_MAX
#define UINT_FAST8_MAX     UINT8_MAX
#define UINT_FAST16_MAX    UINT32_MAX
#define UINT_FAST32_MAX    UINT32_MAX
#define UINT_FAST64_MAX    UINT64_MAX

Symbols

Definition	Description
INT_FAST8_MIN	Minimum value of int_fast8_t
INT_FAST8_MAX	Maximum value of int_fast8_t
INT_FAST16_MIN	Minimum value of int_fast16_t
INT_FAST16_MAX	Maximum value of int_fast16_t
INT_FAST32_MIN	Minimum value of int_fast32_t
INT_FAST32_MAX	Maximum value of int_fast32_t
INT_FAST64_MIN	Minimum value of int_fast64_t
INT_FAST64_MAX	Maximum value of int_fast64_t
UINT_FAST8_MAX	Maximum value of uint_fast8_t
UINT_FAST16_MAX	Maximum value of uint_fast16_t
UINT_FAST32_MAX	Maximum value of uint_fast32_t
UINT_FAST64_MAX	Maximum value of uint_fast64_t

4.6.14.1.6. Pointer types minima and maxima

Description

Minimum and maximum values for pointer-related types.

Definition

#define PTRDIFF_MIN    INT64_MIN
#define PTRDIFF_MAX    INT64_MAX
#define SIZE_MAX       INT64_MAX
#define INTPTR_MIN     INT64_MIN
#define INTPTR_MAX     INT64_MAX
#define UINTPTR_MAX    UINT64_MAX

Symbols

Definition	Description
PTRDIFF_MIN	Minimum value of ptrdiff_t
PTRDIFF_MAX	Maximum value of ptrdiff_t
SIZE_MAX	Maximum value of size_t
INTPTR_MIN	Minimum value of intptr_t
INTPTR_MAX	Maximum value of intptr_t
UINTPTR_MAX	Maximum value of uintptr_t
PTRDIFF_MIN	Minimum value of ptrdiff_t
PTRDIFF_MAX	Maximum value of ptrdiff_t
SIZE_MAX	Maximum value of size_t
INTPTR_MIN	Minimum value of intptr_t
INTPTR_MAX	Maximum value of intptr_t
UINTPTR_MAX	Maximum value of uintptr_t

4.6.14.1.7. Wide integer minima and maxima

Description

Minimum and maximum values for the wint_t type.

Definition

#define WINT_MIN    (-2147483647L-1)
#define WINT_MAX    2147483647L

Symbols

Definition	Description
WINT_MIN	Minimum value of wint_t
WINT_MAX	Maximum value of wint_t

4.6.14.2. Constant construction macros

4.6.14.2.1. Signed integer construction macros

Description

Macros that create constants of type intx_t.

Definition

#define INT8_C(x)     (x)
#define INT16_C(x)    (x)
#define INT32_C(x)    (x)
#define INT64_C(x)    (x##LL)

Symbols

Definition	Description
INT8_C(x)	Create constant of type int8_t
INT16_C(x)	Create constant of type int16_t
INT32_C(x)	Create constant of type int32_t
INT64_C(x)	Create constant of type int64_t

4.6.14.2.2. Unsigned integer construction macros

Description

Macros that create constants of type uintx_t.

Definition

#define UINT8_C(x)     (x##u)
#define UINT16_C(x)    (x##u)
#define UINT32_C(x)    (x##u)
#define UINT64_C(x)    (x##uLL)

Symbols

Definition	Description
UINT8_C(x)	Create constant of type uint8_t
UINT16_C(x)	Create constant of type uint16_t
UINT32_C(x)	Create constant of type uint32_t
UINT64_C(x)	Create constant of type uint64_t

4.6.14.2.3. Maximal integer construction macros

Description

Macros that create constants of type intmax_t and uintmax_t.

Definition

#define INTMAX_C(x)     (x##LL)
#define UINTMAX_C(x)    (x##uLL)

Symbols

Definition	Description
INTMAX_C(x)	Create constant of type intmax_t
UINTMAX_C(x)	Create constant of type uintmax_t

4.6.15. <stdio.h>

4.6.15.1. Formatted output control strings

The functions in this section that accept a formatted output control string do so according to the specification that follows.

4.6.15.1.1. Composition

The format is composed of zero or more directives: ordinary characters (not %, which are copied unchanged to the output stream; and conversion specifications, each of which results in fetching zero or more subsequent arguments, converting them, if applicable, according to the corresponding conversion specifier, and then writing the result to the output stream.

Each conversion specification is introduced by the character %. After the % the following appear in sequence:

Zero or more flags (in any order) that modify the meaning of the conversion specification.
An optional minimum field width. If the converted value has fewer characters than the field width, it is padded with spaces (by default) on the left (or right, if the left adjustment flag has been given) to the field width. The field width takes the form of an asterisk * or a decimal integer.
An optional precision that gives the minimum number of digits to appear for the d, i, o, u, x, and X conversions, the number of digits to appear after the decimal-point character for e, E, f, and F conversions, the maximum number of significant digits for the g and G conversions, or the maximum number of bytes to be written for s conversions. The precision takes the form of a period . followed either by an asterisk * or by an optional decimal integer; if only the period is specified, the precision is taken as zero. If a precision appears with any other conversion specifier, the behavior is undefined.
An optional length modifier that specifies the size of the argument.
A conversion specifier character that specifies the type of conversion to be applied.

As noted above, a field width, or precision, or both, may be indicated by an asterisk. In this case, an int argument supplies the field width or precision. The arguments specifying field width, or precision, or both, must appear (in that order) before the argument (if any) to be converted. A negative field width argument is taken as a - flag followed by a positive field width. A negative precision argument is taken as if the precision were omitted.

4.6.15.1.2. Flag characters

The flag characters and their meanings are:

Flag	Description
	The result of the conversion is left-justified within the field. The default, if this flag is not specified, is that the result of the conversion is left-justified within the field.
	The result of a signed conversion always begins with a plus or minus sign. The default, if this flag is not specified, is that it begins with a sign only when a negative value is converted.
space	If the first character of a signed conversion is not a sign, or if a signed conversion results in no characters, a space is prefixed to the result. If the space and + flags both appear, the space flag is ignored.
#	The result is converted to an alternative form. For o conversion, it increases the precision, if and only if necessary, to force the first digit of the result to be a zero (if the value and precision are both zero, a single 0 is printed). For x or X conversion, a nonzero result has 0x or 0X prefixed to it. For e, E, f, F, g, and G conversions, the result of converting a floating-point number always contains a decimal-point character, even if no digits follow it. (Normally, a decimal-point character appears in the result of these conversions only if a digit follows it.) For g and F conversions, trailing zeros are not removed from the result. As an extension, when used in p conversion, the results has # prefixed to it. For other conversions, the behavior is undefined.
0	For d, i, o, u, x, X, e, E, f, F, g, and G conversions, leading zeros (following any indication of sign or base) are used to pad to the field width rather than performing space padding, except when converting an infinity or NaN. If the 0 and - flags both appear, the 0 flag is ignored. For d, i, o, u, x, and X conversions, if a precision is specified, the 0 flag is ignored. For other conversions, the behavior is undefined.

4.6.15.1.3. Length modifiers

The length modifiers and their meanings are:

Flag	Description
hh	Specifies that a following d, i, o, u, x, or X conversion specifier applies to a signed char or unsigned char argument (the argument will have been promoted according to the integer promotions, but its value will be converted to signed char or unsigned char before printing); or that a following n conversion specifier applies to a pointer to a signed char argument.
h	Specifies that a following d, i, o, u, x, or X conversion specifier applies to a short int or unsigned short int argument (the argument will have been promoted according to the integer promotions, but its value is converted to short int or unsigned short int before printing); or that a following n conversion specifier applies to a pointer to a short int argument.
l	Specifies that a following d, i, o, u, x, or X conversion specifier applies to a long int or unsigned long int argument; that a following n conversion specifier applies to a pointer to a long int argument; or has no effect on a following e, E, f, F, g, or G conversion specifier.
ll	Specifies that a following d, i, o, u, x, or X conversion specifier applies to a long long int or unsigned long long int argument; that a following n conversion specifier applies to a pointer to a long long int argument.

If a length modifier appears with any conversion specifier other than as specified above, the behavior is undefined.

4.6.15.1.4. Conversion specifiers

The conversion specifiers and their meanings are:

Flag	Description
d, i	The argument is converted to signed decimal in the style [-]dddd. The precision specifies the minimum number of digits to appear; if the value being converted can be represented in fewer digits, it is expanded with leading spaces. The default precision is one. The result of converting a zero value with a precision of zero is no characters.
o, u, x, X	The unsigned argument is converted to unsigned octal for o, unsigned decimal for u, or unsigned hexadecimal notation for x or X in the style dddd the letters abcdef are used for x conversion and the letters ABCDEF for X conversion. The precision specifies the minimum number of digits to appear; if the value being converted can be represented in fewer digits, it is expanded with leading spaces. The default precision is one. The result of converting a zero value with a precision of zero is no characters.
f, F	A double argument representing a floating-point number is converted to decimal notation in the style [-]ddd.ddd, where the number of digits after the decimal-point character is equal to the precision specification. If the precision is missing, it is taken as 6; if the precision is zero and the # flag is not specified, no decimal-point character appears. If a decimal-point character appears, at least one digit appears before it. The value is rounded to the appropriate number of digits. A double argument representing an infinity is converted to inf. A double argument representing a NaN is converted to nan. The F conversion specifier produces INF or NAN instead of inf or nan, respectively.
e, E	A double argument representing a floating-point number is converted in the style [-]d.ddde±dd, where there is one digit (which is nonzero if the argument is nonzero) before the decimal-point character and the number of digits after it is equal to the precision; if the precision is missing, it is taken as 6; if the precision is zero and the # flag is not specified, no decimal-point character appears. The value is rounded to the appropriate number of digits. The E conversion specifier produces a number with E instead of e introducing the exponent. The exponent always contains at least two digits, and only as many more digits as necessary to represent the exponent. If the value is zero, the exponent is zero. A double argument representing an infinity is converted to inf. A double argument representing a NaN is converted to nan. The E conversion specifier produces INF or NAN instead of inf or nan, respectively.
g, G	A double argument representing a floating-point number is converted in style f or e (or in style F or e in the case of a G conversion specifier), with the precision specifying the number of significant digits. If the precision is zero, it is taken as one. The style used depends on the value converted; style e (or E) is used only if the exponent resulting from such a conversion is less than -4 or greater than or equal to the precision. Trailing zeros are removed from the fractional portion of the result unless the # flag is specified; a decimal-point character appears only if it is followed by a digit. A double argument representing an infinity is converted to inf. A double argument representing a NaN is converted to nan. The G conversion specifier produces INF or NAN instead of inf or nan, respectively.
c	The argument is converted to an unsigned char, and the resulting character is written.
s	The argument is be a pointer to the initial element of an array of character type. Characters from the array are written up to (but not including) the terminating null character. If the precision is specified, no more than that many characters are written. If the precision is not specified or is greater than the size of the array, the array must contain a null character.
p	The argument is a pointer to void. The value of the pointer is converted in the same format as the x conversion specifier with a fixed precision of 2sizeof(void ).
n	The argument is a pointer to a signed integer into which is written the number of characters written to the output stream so far by the call to the formatting function. No argument is converted, but one is consumed. If the conversion specification includes any flags, a field width, or a precision, the behavior is undefined.
%	A % character is written. No argument is converted.

Note that the C99 width modifier l used in conjunction with the c and s conversion specifiers is not supported and nor are the conversion specifiers a and A.

4.6.15.2. Formatted input control strings

The format is composed of zero or more directives: one or more white-space characters, an ordinary character (neither % nor a white-space character), or a conversion specification.

Each conversion specification is introduced by the character %. After the %, the following appear in sequence:

An optional assignment-suppressing character *.
An optional nonzero decimal integer that specifies the maximum field width (in characters).
An optional length modifier that specifies the size of the receiving object.
A conversion specifier character that specifies the type of conversion to be applied.

The formatted input function executes each directive of the format in turn. If a directive fails, the function returns. Failures are described as input failures (because of the occurrence of an encoding error or the unavailability of input characters), or matching failures (because of inappropriate input).

A directive composed of white-space character(s) is executed by reading input up to the first non-white-space character (which remains unread), or until no more characters can be read.

A directive that is an ordinary character is executed by reading the next characters of the stream. If any of those characters differ from the ones composing the directive, the directive fails and the differing and subsequent characters remain unread. Similarly, if end-of-file, an encoding error, or a read error prevents a character from being read, the directive fails.

A directive that is a conversion specification defines a set of matching input sequences, as described below for each specifier. A conversion specification is executed in the following steps:

Input white-space characters (as specified by the isspace() function) are skipped, unless the specification includes a [, c, or n specifier.
An input item is read from the stream, unless the specification includes an n specifier. An input item is defined as the longest sequence of input characters which does not exceed any specified field width and which is, or is a prefix of, a matching input sequence. The first character, if any, after the input item remains unread. If the length of the input item is zero, the execution of the directive fails; this condition is a matching failure unless end-of-file, an encoding error, or a read error prevented input from the stream, in which case it is an input failure.
Except in the case of a % specifier, the input item (or, in the case of a %n directive, the count of input characters) is converted to a type appropriate to the conversion specifier. If the input item is not a matching sequence, the execution of the directive fails: this condition is a matching failure. Unless assignment suppression was indicated by a *, the result of the conversion is placed in the object pointed to by the first argument following the format argument that has not already received a conversion result. If this object does not have an appropriate type, or if the result of the conversion cannot be represented in the object, the behavior is undefined.

4.6.15.2.1. Length modifiers

The length modifiers and their meanings are:

Flag	Description
hh	Specifies that a following d, i, o, u, x, X, or n conversion specifier applies to an argument with type pointer to signed char or pointer to unsigned char.
h	Specifies that a following d, i, o, u, x, X, or n conversion specifier applies to an argument with type pointer to short int or unsigned short int.
l	Specifies that a following d, i, o, u, x, X, or n conversion specifier applies to an argument with type pointer to long int or unsigned long int; that a following e, E, f, F, g, or G conversion specifier applies to an argument with type pointer to double.
ll	Specifies that a following d, i, o, u, x, X, or n conversion specifier applies to an argument with type pointer to long long int or unsigned long long int.

If a length modifier appears with any conversion specifier other than as specified above, the behavior is undefined. Note that the C99 length modifiers j, z, and t are not supported.

4.6.15.2.2. Conversion specifiers

Flag	Description
d	Matches an optionally signed decimal integer, whose format is the same as expected for the subject sequence of the strtol() function with the value 10 for the base argument. The corresponding argument must be a pointer to signed integer.
i	Matches an optionally signed integer, whose format is the same as expected for the subject sequence of the strtol() function with the value zero for the base argument. The corresponding argument must be a pointer to signed integer.
o	Matches an optionally signed octal integer, whose format is the same as expected for the subject sequence of the strtol() function with the value 18 for the base argument. The corresponding argument must be a pointer to signed integer.
u	Matches an optionally signed decimal integer, whose format is the same as expected for the subject sequence of the strtoul() function with the value 10 for the base argument. The corresponding argument must be a pointer to unsigned integer.
x	Matches an optionally signed hexadecimal integer, whose format is the same as expected for the subject sequence of the strtoul() function with the value 16 for the base argument. The corresponding argument must be a pointer to unsigned integer.
e, f, g	Matches an optionally signed floating-point number whose format is the same as expected for the subject sequence of the strtod() function. The corresponding argument shall be a pointer to floating.
c	Matches a sequence of characters of exactly the number specified by the field width (one if no field width is present in the directive). The corresponding argument must be a pointer to the initial element of a character array large enough to accept the sequence. No null character is added.
s	Matches a sequence of non-white-space characters The corresponding argument must be a pointer to the initial element of a character array large enough to accept the sequence and a terminating null character, which will be added automatically.
[	Matches a nonempty sequence of characters from a set of expected characters (the scanset). The corresponding argument must be a pointer to the initial element of a character array large enough to accept the sequence and a terminating null character, which will be added automatically. The conversion specifier includes all subsequent characters in the format string, up to and including the matching right bracket ]. The characters between the brackets (the scanlist) compose the scanset, unless the character after the left bracket is a circumflex ^, in which case the scanset contains all characters that do not appear in the scanlist between the circumflex and the right bracket. If the conversion specifier begins with [] or[^], the right bracket character is in the scanlist and the next following right bracket character is the matching right bracket that ends the specification; otherwise the first following right bracket character is the one that ends the specification. If a - character is in the scanlist and is not the first, nor the second where the first character is a ^, nor the last character, it is treated as a member of the scanset.
p	Reads a sequence output by the corresponding %p formatted output conversion. The corresponding argument must be a pointer to a pointer to void.
n	No input is consumed. The corresponding argument shall be a pointer to signed integer into which is to be written the number of characters read from the input stream so far by this call to the formatted input function. Execution of a %n directive does not increment the assignment count returned at the completion of execution of the fscanf function. No argument is converted, but one is consumed. If the conversion specification includes an assignment-suppressing character or a field width, the behavior is undefined.
%	Matches a single % character; no conversion or assignment occurs.

Note that the C99 width modifier l used in conjunction with the c, s, and [ conversion specifiers is not supported and nor are the conversion specifiers a and A.

4.6.15.3. Character and string I/O functions

Function	Description
getchar()	Read character from standard input.
gets()	Read string from standard input.
putc()	Write character to file.
putchar()	Write character to standard output.
puts()	Write string to standard output.

4.6.15.3.1. getchar()

Description

Read character from standard input.

Prototype

int getchar(void);

Return value

If the stream is at end-of-file or a read error occurs, returns EOF, otherwise a nonnegative value.

Additional information

Reads a single character from the standard input stream.

4.6.15.3.2. gets()

Description

Read string from standard input.

Prototype

char *gets(char * s);

Parameters

Parameter	Description
s	Pointer to object that receives the string.

Return value

Returns s if successful. If end-of-file is encountered and no characters have been read into the array, the contents of the array remain unchanged and a null pointer is returned. If a read error occurs during the operation, the array contents are indeterminate and a null null pointer is return.

Additional information

This function reads characters from standard input into the array pointed to by s until end-of-file is encountered or a new-line character is read. Any new-line character is discarded, and a null character is written immediately after the last character read into the array.

4.6.15.3.3. putc()

Description

Write character to file.

Prototype

int putc(int    c,
         FILE * stream);

Parameters

Parameter	Description
c	Character to write.
stream	Pointer to stream to write to.

Return value

If no error, the character written. If a write error occurs, returns EOF.

Additional information

Writes the character c to stream.

4.6.15.3.4. putchar()

Description

Write character to standard output.

Prototype

int putchar(int c);

Parameters

Parameter	Description
c	Character to write.

Return value

If no error, the character written. If a write error occurs, returns EOF.

Additional information

Writes the character c to the standard output stream.

4.6.15.3.5. puts()

Description

Write string to standard output.

Prototype

int puts(const char * s);

Parameters

Parameter	Description
s	Pointer to zero-terminated string.

Return value

Returns EOF if a write error occurs; otherwise it returns a nonnegative value.

Additional information

Writes the string pointed to by s to the standard output stream using putchar() and appends a new-line character to the output. The terminating null character is not written.

4.6.15.4. Formatted input functions

Function	Description
scanf()	Formatted read from standard input.
sscanf()	Formatted read from string.
vscanf()	Formatted read from standard input, variadic.
vsscanf()	Formatted read from string, variadic.

4.6.15.4.1. scanf()

Description

Formatted read from standard input.

Prototype

int scanf(const char * format,
                       ...);

Parameters

Parameter	Description
format	Pointer to zero-terminated format control string.

Return value

Returns the value of the macro EOF if an input failure occurs before any conversion. Otherwise, returns the number of input items assigned, which can be fewer than provided for, or even zero, in the event of an early matching failure.

Additional information

Reads input from the standard input stream under control of the string pointed to by format that specifies the admissible input sequences and how they are to be converted for assignment, using subsequent arguments as pointers to the objects to receive the converted input.

If there are insufficient arguments for the format, the behavior is undefined. If the format is exhausted while arguments remain, the excess arguments are evaluated but are otherwise ignored.

4.6.15.4.2. sscanf()

Description

Formatted read from string.

Prototype

int sscanf(const char * s,
           const char * format,
                        ...);

Parameters

Parameter	Description
s	Pointer to string to read from.
format	Pointer to zero-terminated format control string.

Return value

Returns the value of the macro EOF if an input failure occurs before any conversion. Otherwise, returns the number of input items assigned, which can be fewer than provided for, or even zero, in the event of an early matching failure.

Additional information

Reads input from the string s under control of the string pointed to by format that specifies the admissible input sequences and how they are to be converted for assignment, using subsequent arguments as pointers to the objects to receive the converted input.

If there are insufficient arguments for the format, the behavior is undefined. If the format is exhausted while arguments remain, the excess arguments are evaluated but are otherwise ignored.

4.6.15.4.3. vscanf()

Description

Formatted read from standard input, variadic.

Prototype

int vscanf(const char    * format,
                 va_list   arg);

Parameters

Parameter	Description
format	Pointer to zero-terminated format control string.
arg	Variable parameter list.

Return value

Returns the value of the macro EOF if an input failure occurs before any conversion. Otherwise, returns the number of input items assigned, which can be fewer than provided for, or even zero, in the event of an early matching failure.

Additional information

Reads input from the standard input stream under control of the string pointed to by format that specifies the admissible input sequences and how they are to be converted for assignment, using subsequent arguments as pointers to the objects to receive the converted input. Before calling vscanf(), arg must be initialized by the va_start() macro (and possibly subsequent va_arg() calls). vscanf() does not invoke the va_end() macro.

If there are insufficient arguments for the format, the behavior is undefined.

4.6.15.4.4. vsscanf()

Description

Formatted read from string, variadic.

Prototype

int vsscanf(const char    * s,
            const char    * format,
                  va_list   arg);

Parameters

Parameter	Description
s	Pointer to string to read from.
format	Pointer to zero-terminated format control string.
arg	Variable parameter list.

Return value

Returns the value of the macro EOF if an input failure occurs before any conversion. Otherwise, returns the number of input items assigned, which can be fewer than provided for, or even zero, in the event of an early matching failure.

Additional information

Reads input from the standard input stream under control of the string pointed to by format that specifies the admissible input sequences and how they are to be converted for assignment, using subsequent arguments as pointers to the objects to receive the converted input. Before calling vsscanf(), arg must be initialized by the va_start() macro (and possibly subsequent va_arg() calls). vsscanf() does not invoke the va_end() macro.

If there are insufficient arguments for the format, the behavior is undefined.

4.6.15.5. Formatted output functions

Function	Description
printf()	Formatted write to standard output.
sprintf()	Formatted write to string.
snprintf()	Formatted write to string, limit length.
vprintf()	Formatted write to standard output, variadic.
vsprintf()	Formatted write to string, variadic.
vsnprintf()	Formatted write to string, limit length, variadic.

4.6.15.5.1. printf()

Description

Formatted write to standard output.

Prototype

int printf(const char * format,
                        ...);

Parameters

Parameter	Description
format	Pointer to zero-terminated format control string.

Return value

Returns the number of characters written, or a negative value if an output or encoding error occurred.

Additional information

Writes to the standard output stream under control of the string pointed to by format that specifies how subsequent arguments are converted for output.

If there are insufficient arguments for the format, the behavior is undefined. If the format is exhausted while arguments remain, the excess arguments are evaluated but are otherwise ignored.

4.6.15.5.2. sprintf()

Description

Formatted write to string.

Prototype

int sprintf(      char * s,
            const char * format,
                         ...);

Parameters

Parameter	Description
s	Pointer to array that receives the formatted output.
format	Pointer to zero-terminated format control string.

Return value

Returns number of characters written to s (not counting the terminating null), or a negative value if an output or encoding error occurred.

Additional information

Writes to the string pointed to by s under control of the string pointed to by format that specifies how subsequent arguments are converted for output. A null character is written at the end of the characters written; it is not counted as part of the returned value.

If there are insufficient arguments for the format, the behavior is undefined. If the format is exhausted while arguments remain, the excess arguments are evaluated but are otherwise ignored.

If copying takes place between objects that overlap, the behavior is undefined.

4.6.15.5.3. snprintf()

Description

Formatted write to string, limit length.

Prototype

int snprintf(      char   * s,
                   size_t   n,
             const char   * format,
                            ...);

Parameters

Parameter	Description
s	Pointer to array that receives the formatted output.
n	Maximum number of characters to write to the array pointed to by s.
format	Pointer to zero-terminated format control string.

Return value

Returns the number of characters that would have been written had n been sufficiently large, not counting the terminating null character, or a negative value if an encoding error occurred. Thus, the null-terminated output has been completely written if and only if the returned value is nonnegative and less than n.

Additional information

Writes to the string pointed to by s under control of the string pointed to by format that specifies how subsequent arguments are converted for output.

If n is zero, nothing is written, and s can be a null pointer. Otherwise, output characters beyond count n-1 are discarded rather than being written to the array, and a null character is written at the end of the characters actually written into the array. A null character is written at the end of the conversion; it is not counted as part of the returned value.

If there are insufficient arguments for the format, the behavior is undefined. If the format is exhausted while arguments remain, the excess arguments are evaluated but are otherwise ignored.

If copying takes place between objects that overlap, the behavior is undefined.

4.6.15.5.4. vprintf()

Description

Formatted write to standard output, variadic.

Prototype

int vprintf(const char    * format,
                  va_list   arg);

Parameters

Parameter	Description
format	Pointer to zero-terminated format control string.
arg	Variable parameter list.

Return value

Returns the number of characters written, or a negative value if an output or encoding error occurred.

Additional information

Writes to the standard output stream using under control of the string pointed to by format that specifies how subsequent arguments are converted for output. Before calling vprintf(), arg must be initialized by the va_start macro (and possibly subsequent va_arg calls). vprintf() does not invoke the va_end macro.

4.6.15.5.5. vsprintf()

Description

Formatted write to string, variadic.

Prototype

int vsprintf(      char    * s,
             const char    * format,
                   va_list   arg);

Parameters

Parameter	Description
s	Pointer to array that receives the formatted output.
format	Pointer to zero-terminated format control string.
arg	Variable parameter list.

Return value

Returns number of characters written to s (not counting the terminating null), or a negative value if an output or encoding error occurred.

Additional information

Writes to the string pointed to by s under control of the string pointed to by format that specifies how subsequent arguments are converted for output. A null character is written at the end of the characters written; it is not counted as part of the returned value.

Before calling vsprintf(), arg must be initialized by the va_start macro (and possibly subsequent va_arg calls). vsprintf() does not invoke the va_end macro.

If there are insufficient arguments for the format, the behavior is undefined. If the format is exhausted while arguments remain, the excess arguments are evaluated but are otherwise ignored.

If copying takes place between objects that overlap, the behavior is undefined.

Notes

This is equivalent to sprintf() with the variable argument list replaced by arg.

4.6.15.5.6. vsnprintf()

Description

Formatted write to string, limit length, variadic.

Prototype

int vsnprintf(      char    * s,
                    size_t    n,
              const char    * format,
                    va_list   arg);

Parameters

Parameter	Description
s	Pointer to array that receives the formatted output.
n	Maximum number of characters to write to the array pointed to by s.
format	Pointer to zero-terminated format control string.
arg	Variable parameter list.

Return value

Returns the number of characters that would have been written had n been sufficiently large, not counting the terminating null character, or a negative value if an encoding error occurred. Thus, the null-terminated output has been completely written if and only if the returned value is nonnegative and less than n.

Additional information

Writes to the string pointed to by s under control of the string pointed to by format that specifies how subsequent arguments are converted for output. Before calling vsnprintf(), arg must be initialized by the va_start macro (and possibly subsequent va_arg() calls). vsnprintf() does not invoke the va_end macro.

If n is zero, nothing is written, and s can be a null pointer. Otherwise, output characters beyond count n-1 are discarded rather than being written to the array, and a null character is written at the end of the characters actually written into the array. A null character is written at the end of the conversion; it is not counted as part of the returned value.

If there are insufficient arguments for the format, the behavior is undefined. If the format is exhausted while arguments remain, the excess arguments are evaluated but are otherwise ignored.

If copying takes place between objects that overlap, the behavior is undefined.

Notes

This is equivalent to snprintf() with the variable argument list replaced by arg.

4.6.16. <stdlib.h>

4.6.16.1. Process control functions

Function	Description
atexit()	Set function to be called on exit.
abort()	Abort execution.

4.6.16.1.1. atexit()

Description

Set function to be called on exit.

Prototype

int atexit(__SEGGER_RTL_exit_func fn);

Parameters

Parameter	Description
fn	Function to register.

Return value

= 0	Success registering function.
≠ 0	Did not register function.

Additional information

Registers function fn to be called when the application has exited. The functions registered with atexit() are executed in reverse order of their registration.

4.6.16.1.2. abort()

Description

Abort execution.

Prototype

void abort(void);

Additional information

Calls exit() with the exit status -1.

4.6.16.2. Integer arithmetic functions

Function	Description
abs()	Calculate absolute value, int.
labs()	Calculate absolute value, long.
llabs()	Calculate absolute value, long long.
div()	Divide returning quotient and remainder, int.
ldiv()	Divide returning quotient and remainder, long.
lldiv()	Divide returning quotient and remainder, long long.

4.6.16.2.1. abs()

Description

Calculate absolute value, int.

Prototype

int abs(int Value);

Parameters

Parameter	Description
Value	Integer value.

Return value

The absolute value of the integer argument Value.

4.6.16.2.2. labs()

Description

Calculate absolute value, long.

Prototype

long int labs(long int Value);

Parameters

Parameter	Description
Value	Long integer value.

Return value

The absolute value of the long integer argument Value.

4.6.16.2.3. llabs()

Description

Calculate absolute value, long long.

Prototype

long long int llabs(long long int Value);

Parameters

Parameter	Description
Value	Long long integer value.

Return value

The absolute value of the long long integer argument Value.

4.6.16.2.4. div()

Description

Divide returning quotient and remainder, int.

Prototype

div_t div(int Numer,
          int Denom);

Parameters

Parameter	Description
Numer	Numerator.
Denom	Demoninator.

Return value

Returns a structure of type div_t comprising both the quotient and the remainder. The structures contain the members quot (the quotient) and rem (the remainder), each of which has the same type as the arguments Numer and Denom. If either part of the result cannot be represented, the behavior is undefined.

Additional information

This computes Numer divided by Denom and Numer modulo Denom in a single operation.

See also

div_t

4.6.16.2.5. ldiv()

Description

Divide returning quotient and remainder, long.

Prototype

ldiv_t ldiv(long Numer,
            long Denom);

Parameters

Parameter	Description
Numer	Numerator.
Denom	Demoninator.

Return value

Returns a structure of type ldiv_t comprising both the quotient and the remainder. The structures contain the members quot (the quotient) and rem (the remainder), each of which has the same type as the arguments Numer and Denom. If either part of the result cannot be represented, the behavior is undefined.

Additional information

This computes Numer divided by Denom and Numer modulo Denom in a single operation.

See also

ldiv_t

4.6.16.2.6. lldiv()

Description

Divide returning quotient and remainder, long long.

Prototype

lldiv_t lldiv(long long Numer,
              long long Denom);

Parameters

Parameter	Description
Numer	Numerator.
Denom	Demoninator.

Return value

Returns a structure of type lldiv_t comprising both the quotient and the remainder. The structures contain the members quot (the quotient) and rem (the remainder), each of which has the same type as the arguments Numer and Denom. If either part of the result cannot be represented, the behavior is undefined.

Additional information

This computes Numer divided by Denom and Numer modulo Denom in a single operation.

See also

lldiv_t

4.6.16.3. Pseudo-random sequence generation functions

Function	Description
rand()	Return next random number in sequence.
srand()	Set seed of random number sequence.

4.6.16.3.1. rand()

Description

Return next random number in sequence.

Prototype

int rand(void);

Return value

Returns the computed pseudo-random integer.

Additional information

This computes a sequence of pseudo-random integers in the range 0 to RAND_MAX.

See also

srand()

4.6.16.3.2. srand()

Description

Set seed of random number sequence.

Prototype

void srand(unsigned s);

Parameters

Parameter	Description
s	New seed value for pseudo-random sequence.

Additional information

This uses the argument Seed as a seed for a new sequence of pseudo-random numbers to be returned by subsequent calls to rand(). If srand() is called with the same seed value, the same sequence of pseudo-random numbers is generated.

If rand() is called before any calls to srand() have been made, a sequence is generated as if srand() is first called with a seed value of 1.

See also

rand()

4.6.16.4. Memory allocation functions

Function	Description
malloc()	Allocate space for single object.
calloc()	Allocate space for multiple objects and zero them.
realloc()	Resize or allocate memory space.
free()	Free allocated memory for reuse.

4.6.16.4.1. malloc()

Description

Allocate space for single object.

Prototype

void *malloc(size_t sz);

Parameters

Parameter	Description
sz	Number of characters to allocate for the object.

Return value

Returns a null pointer if the space for the object cannot be allocated from free memory; if space for the object can be allocated, malloc() returns a pointer to the start of the allocated space.

Additional information

Allocates space for an object whose size is specified by sz and whose value is indeterminate.

4.6.16.4.2. calloc()

Description

Allocate space for multiple objects and zero them.

Prototype

void *calloc(size_t nobj,
             size_t sz);

Parameters

Parameter	Description
nobj	Number of objects to allocate.
sz	Number of characters to allocate per object.

Return value

Returns a null pointer if the space for the object cannot be allocated from free memory; if space for the object can be allocated, malloc() returns a pointer to the start of the allocated space.

Additional information

Allocates space for an array of nobj objects, each of whose size is sz. The space is initialized to all zero bits.

4.6.16.4.3. realloc()

Description

Resize or allocate memory space.

Prototype

void *realloc(void   * ptr,
              size_t   sz);

Parameters

Parameter	Description
ptr	Pointer to resize, or NULL to allocate.
sz	New size of object.

Return value

Returns a pointer to the new object (which may have the same value as a pointer to the old object), or a null pointer if the new object could not be allocated.

Additional information

Deallocates the old object pointed to by ptr and returns a pointer to a new object that has the size specified by sz. The contents of the new object is identical to that of the old object prior to deallocation, up to the lesser of the new and old sizes. Any bytes in the new object beyond the size of the old object have indeterminate values.

If ptr is a null pointer, realloc() behaves like malloc() for the specified size. If memory for the new object cannot be allocated, the old object is not deallocated and its value is unchanged.

If ptr does not match a pointer earlier returned by calloc(), malloc(), or realloc(), or if the space has been deallocated by a call to free() or realloc(), the behavior is undefined.

4.6.16.4.4. free()

Description

Free allocated memory for reuse.

Prototype

void free(void * ptr);

Parameters

Parameter	Description
ptr	Pointer to object to free.

Additional information

Causes the space pointed to by ptr to be deallocated, that is, made available for further allocation. If ptr is a null pointer, no action occurs.

If ptr does not match a pointer earlier returned by calloc(), malloc(), or realloc(), or if the space has been deallocated by a call to free() or realloc(), the behavior is undefined.

4.6.16.5. Search and sort functions

Function	Description
qsort()	Sort array.
bsearch()	Search sorted array.

4.6.16.5.1. qsort()

Description

Sort array.

Prototype

void qsort(void   * base,
           size_t   nmemb,
           size_t   sz,
           int      ( *compare)(const void * elem1 , const void * elem2 ));

Parameters

Parameter	Description
base	Pointer to the start of the array.
nmemb	Number of array elements.
sz	Number of characters per array element.
compare	Pointer to element comparison function.

Additional information

Sorts the array pointed to by base using the compare function. The array should have nmemb elements of sz bytes. The compare function should return a negative value if the first parameter is less than the second parameter, zero if the parameters are equal, and a positive value if the first parameter is greater than the second parameter.

4.6.16.5.2. bsearch()

Description

Search sorted array.

Prototype

void *bsearch
            (const void   * key,
             const void   * base,
                   size_t   nmemb,
                   size_t   sz,
                   int      ( *compare)(const void * elem1 , const void * elem2 ));

Parameters

Parameter	Description
key	Pointer to object to search for.
base	Pointer to the start of the array.
nmemb	Number of array elements.
sz	Number of characters per array element.
compare	Pointer to element comparison function.

Return value

= NULL	Key not found.
≠ NULL	Pointer to found object.

Additional information

Searches the array pointed to by base for the specified key and returns a pointer to the first entry that matches, or null if no match. The array should have nmemb elements of sz bytes and be sorted by the same algorithm as the compare function.

The compare function should return a negative value if the first parameter is less than second parameter, zero if the parameters are equal, and a positive value if the first parameter is greater than the second parameter.

4.6.16.6. Number to string conversions

Function	Description
itoa()	Convert to string, int.
ltoa()	Convert to string, long.
lltoa()	Convert to string, long long.
utoa()	Convert to string, unsigned.
ultoa()	Convert to string, unsigned long.
ulltoa()	Convert to string, unsigned long long.

4.6.16.6.1. itoa()

Description

Convert to string, int.

Prototype

char *itoa(int    val,
           char * buf,
           int    radix);

Parameters

Parameter	Description
val	Value to convert.
buf	Pointer to array of characters that receives the string.
radix	Number base to use for conversion, 2 to 36.

Return value

Returns buf.

Additional information

Converts val to a string in base radix and places the result in buf which must be large enough to hold the output. If radix is greater than 36, the result is undefined.

If val is negative and radix is 10, the string has a leading minus sign (-); for all other values of radix, value is considered unsigned and never has a leading minus sign.

Notes

This is a non-standard function. Even though this function is commonly used by compilers on other platforms, there is no guarantee that this function will behave the same on all platforms, in all cases.

4.6.16.6.2. ltoa()

Description

Convert to string, long.

Prototype

char *ltoa(long   val,
           char * buf,
           int    radix);

Parameters

Parameter	Description
val	Value to convert.
buf	Pointer to array of characters that receives the string.
radix	Number base to use for conversion, 2 to 36.

Return value

Returns buf.

Additional information

Converts val to a string in base radix and places the result in buf which must be large enough to hold the output. If radix is greater than 36, the result is undefined.

If val is negative and radix is 10, the string has a leading minus sign (-); for all other values of radix, value is considered unsigned and never has a leading minus sign.

Notes

This is a non-standard function. Even though this function is commonly used by compilers on other platforms, there is no guarantee that this function will behave the same on all platforms, in all cases.

4.6.16.6.3. lltoa()

Description

Convert to string, long long.

Prototype

char *lltoa(long long   val,
            char      * buf,
            int         radix);

Parameters

Parameter	Description
val	Value to convert.
buf	Pointer to array of characters that receives the string.
radix	Number base to use for conversion, 2 to 36.

Return value

Returns buf.

Additional information

Converts val to a string in base radix and places the result in buf which must be large enough to hold the output. If radix is greater than 36, the result is undefined.

If val is negative and radix is 10, the string has a leading minus sign (-); for all other values of radix, value is considered unsigned and never has a leading minus sign.

Notes

This is a non-standard function. Even though this function is commonly used by compilers on other platforms, there is no guarantee that this function will behave the same on all platforms, in all cases.

4.6.16.6.4. utoa()

Description

Convert to string, unsigned.

Prototype

char *utoa(unsigned   val,
           char     * buf,
           int        radix);

Parameters

Parameter	Description
val	Value to convert.
buf	Pointer to array of characters that receives the string.
radix	Number base to use for conversion, 2 to 36.

Return value

Returns buf.

Additional information

Converts val to a string in base radix and places the result in buf which must be large enough to hold the output. If radix is greater than 36, the result is undefined.

Notes

This is a non-standard function. Even though this function is commonly used by compilers on other platforms, there is no guarantee that this function will behave the same on all platforms, in all cases.

4.6.16.6.5. ultoa()

Description

Convert to string, unsigned long.

Prototype

char *ultoa(unsigned long   val,
            char          * buf,
            int             radix);

Parameters

Parameter	Description
val	Value to convert.
buf	Pointer to array of characters that receives the string.
radix	Number base to use for conversion, 2 to 36.

Return value

Returns buf.

Additional information

Converts val to a string in base radix and places the result in buf which must be large enough to hold the output. If radix is greater than 36, the result is undefined.

Notes

This is a non-standard function. Even though this function is commonly used by compilers on other platforms, there is no guarantee that this function will behave the same on all platforms, in all cases.

4.6.16.6.6. ulltoa()

Description

Convert to string, unsigned long long.

Prototype

char *ulltoa(unsigned long long   val,
             char               * buf,
             int                  radix);

Parameters

Parameter	Description
val	Value to convert.
buf	Pointer to array of characters that receives the string.
radix	Number base to use for conversion, 2 to 36.

Return value

Returns buf.

Additional information

Converts val to a string in base radix and places the result in buf which must be large enough to hold the output. If radix is greater than 36, the result is undefined.

Notes

This is a non-standard function. Even though this function is commonly used by compilers on other platforms, there is no guarantee that this function will behave the same on all platforms, in all cases.

4.6.16.7. String to number conversions

Function	Description
atoi()	Convert to number, int.
atol()	Convert to number, long.
atoll()	Convert to number, long long.
atof()	Convert to number, double.
strtol()	Convert to number, long.
strtoll()	Convert to number, long long.
strtoul()	Convert to number, unsigned long.
strtoull()	Convert to number, unsigned long long.
strtof()	Convert to number, float.
strtod()	Convert to number, double.
strtold()	Convert to number, long double.

4.6.16.7.1. atoi()

Description

Convert to number, int.

Prototype

int atoi(const char * nptr);

Parameters

Parameter	Description
nptr	Pointer to string to convert from.

Return value

Returns the converted value, if any. If the value of the result cannot be represented, the behavior is undefined.

Additional information

Converts the initial portion of the string pointed to by nptr to an int representation.

atoi() does not affect the value of errno on an error.

Notes

Except for the behavior on error, atoi() is equivalent to (int)strtol(nptr, NULL, 10).

See also

strtol()

4.6.16.7.2. atol()

Description

Convert to number, long.

Prototype

long int atol(const char * nptr);

Parameters

Parameter	Description
nptr	Pointer to string to convert from.

Return value

Returns the converted value, if any. If the value of the result cannot be represented, the behavior is undefined.

Additional information

Converts the initial portion of the string pointed to by nptr to a long representation.

atol() does not affect the value of errno on an error.

Notes

Except for the behavior on error, atol() is equivalent to strtol(nptr, NULL, 10).

See also

strtol()

4.6.16.7.3. atoll()

Description

Convert to number, long long.

Prototype

long long int atoll(const char * nptr);

Parameters

Parameter	Description
nptr	Pointer to string to convert from.

Return value

Returns the converted value, if any. If the value of the result cannot be represented, the behavior is undefined.

Additional information

Converts the initial portion of the string pointed to by nptr to a long-long representation.

atoll() does not affect the value of errno on an error.

Notes

Except for the behavior on error, atoll() is equivalent to strtoll(nptr, NULL, 10).

See also

strtoll()

4.6.16.7.4. atof()

Description

Convert to number, double.

Prototype

double atof(const char * nptr);

Parameters

Parameter	Description
nptr	Pointer to string to convert from.

Return value

Returns the converted value, if any. If the value of the result cannot be represented, the behavior is undefined.

Additional information

Converts the initial portion of the string pointed to by nptr to an double representation.

atof() does not affect the value of errno on an error.

Notes

Except for the behavior on error, atof() is equivalent to (int)strtod(nptr, NULL).

See also

strtod()

4.6.16.7.5. strtol()

Description

Convert to number, long.

Prototype

long strtol(const char  * nptr,
                  char ** endptr,
                  int     base);

Parameters

Parameter	Description
nptr	Pointer to string to convert from.
endptr	If nonnull, a pointer to object that receives the pointer to the first unconverted character.
base	Radix to use for conversion, 2 to 36.

Return value

Returns the converted value, if any. If no conversion could be performed, zero is returned. If the correct value is outside the range of representable values, LONG_MIN or LONG_MAX is returned according to the sign of the value, if any, and the value of the macro ERANGE is stored in errno.

Additional information

Converts the initial portion of the string pointed to by nptr to a long representation.

First, strtol() decomposes the input string into three parts: an initial, possibly empty, sequence of white-space characters, as specified by isspace(), a subject sequence resembling an integer represented in some radix determined by the value of base, and a final string of one or more unrecognized characters, including the terminating null character of the input string. strtol() then attempts to convert the subject sequence to an integer, and return the result.

When converting, no integer suffix (such as U, L, UL, LL, ULL) is allowed.

If the value of base is zero, the expected form of the subject sequence is an optional plus or minus sign followed by an integer constant.

If the value of base is between 2 and 36 (inclusive), the expected form of the subject sequence is an optional plus or minus sign followed by a sequence of letters and digits representing an integer with the radix specified by base. The letters from a (or A) through z (or Z) represent the values 10 through 35; only letters and digits whose ascribed values are less than that of base are permitted.

If the value of base is 16, the characters “0x” or “0X” may optionally precede the sequence of letters and digits, following the optional sign.

The subject sequence is defined as the longest initial subsequence of the input string, starting with the first non-white-space character, that is of the expected form. The subject sequence contains no characters if the input string is empty or consists entirely of white space, or if the first non-white-space character is other than a sign or a permissible letter or digit.

If the subject sequence has the expected form and the value of base is zero, the sequence of characters starting with the first digit is interpreted as an integer constant. If the subject sequence has the expected form and the value of base is between 2 and 36, it is used as the base for conversion.

If the subject sequence begins with a minus sign, the value resulting from the conversion is negated.

A pointer to the final string is stored in the object pointed to by endptr, provided that endptr is not a null pointer.

If the subject sequence is empty or does not have the expected form, no conversion is performed, the value of nptr is stored in the object pointed to by endptr, provided that endptr is not a null pointer.

4.6.16.7.6. strtoll()

Description

Convert to number, long long.

Prototype

long long strtoll(const char  * nptr,
                        char ** endptr,
                        int     base);

Parameters

Parameter	Description
nptr	Pointer to string to convert from.
endptr	If nonnull, a pointer to object that receives the pointer to the first unconverted character.
base	Radix to use for conversion, 2 to 36.

Return value

Returns the converted value, if any. If no conversion could be performed, zero is returned. If the correct value is outside the range of representable values, LLONG_MIN or LLONG_MAX is returned according to the sign of the value, if any, and the value of the macro ERANGE is stored in errno.

Additional information

Converts the initial portion of the string pointed to by nptr to a long representation.

First, strtoll() decomposes the input string into three parts: an initial, possibly empty, sequence of white-space characters, as specified by isspace(), a subject sequence resembling an integer represented in some radix determined by the value of base, and a final string of one or more unrecognized characters, including the terminating null character of the input string. strtoll() then attempts to convert the subject sequence to an integer, and return the result.