tgmath(3HEAD) (man pages section 3: Library Interfaces and Headers)

man pages section 3: Library Interfaces and Headers

tgmath(3HEAD)

Name

tgmath.h, tgmath– type-generic macros

Synopsis

#include <tgmath.h>

Description

The <tgmath.h> header includes the headers <math.h> and <complex.h> and defines several type-generic macros.

Of the functions contained within the <math.h> and <complex.h> headers without an f (float) or l (long double) suffix, several have one or more parameters whose corresponding real type is double. For each such function except modf(3M), there is a corresponding type-generic macro. The parameters whose corresponding real type is double in the function synopsis are generic parameters. Use of the macro invokes a function whose corresponding real type and type domain are determined by the arguments for the generic parameters.

Use of the macro invokes a function whose generic parameters have the corresponding real type determined as follows:

First, if any argument for generic parameters has type long double, the type determined is long double.
Otherwise, if any argument for generic parameters has type double or is of integer type, the type determined is double.
Otherwise, the type determined is float.

For each unsuffixed function in the <math.h> header for which there is a function in the <complex.h> header with the same name except for a c prefix, the corresponding type-generic macro (for both functions) has the same name as the function in the <math.h> header. The corresponding type-generic macro for fabs() and cabs() is fabs().

<`math.h`> Function	<`complex.h`> Function	Type-Generic Macro
`acos()`	`cacos()`	`acos()`
`asin()`	`casin()`	`asin()`
`atan()`	`catan()`	`atan()`
`acosh()`	`cacosh()`	`acosh()`
`asinh()`	`casinh()`	`asinh()`
`atanh()`	`catanh()`	`atanh()`
`cos()`	`ccos()`	`cos()`
`sin()`	`csin()`	`sin()`
`tan()`	`ctan()`	`tan()`
`cosh()`	`ccosh()`	`cosh()`
`sinh()`	`csinh()`	`sinh()`
`tanh()`	`ctanh()`	`tanh()`
`exp()`	`cexp()`	`exp()`
`log()`	`clog()`	`log()`
`pow()`	`cpow()`	`pow()`
`sqrt()`	`csqrt()`	`sqrt()`
`fabs()`	`cfabs()`	`fabs()`

If at least one argument for a generic parameter is complex, then use of the macro invokes a complex function; otherwise, use of the macro invokes a real function.

For each unsuffixed function in the <math.h> header without a c-prefixed counterpart in the <complex.h> header, the corresponding type-generic macro has the same name as the function. These type-generic macros are:

atan2()       fma()     llround()       remainder()
cbrt()        fmax()    log10()         remquo()
ceil()        fmin()    log1p()         rint()
copysign()    fmod()    log2()          round()
erf()         frexp()   logb()          scalbn()
erfc()        hypot()   lrint()         scalbln()
exp2()        ilogb()   lround()        tgamma()
expm1()       ldexp()   nearbyint()     trunc()
fdim()        lgamma()  nextafter()
floor()       llrint()  nexttoward()

If all arguments for generic parameters are real, then use of the macro invokes a real function; otherwise, use of the macro results in undefined behavior.

For each unsuffixed function in the <complex.h> header that is not a c-prefixed counterpart to a function in the <math.h> header, the corresponding type-generic macro has the same name as the function. These type-generic macros are:

carg()
cimag()
conj()
cproj()
creal()

Use of the macro with any real or complex argument invokes a complex function.

Usage

Functions invoked by use of type-generic macros are invoked with the declarations listed below.

#include <tgmath.h>
int n;
float f;
double d;
long double ld;
float complex fc;
double complex dc;
long double complex ldc;

The following are the type-generic macros that invoke the functions that are invoked with the preceding declarations.

Macro	Use Invokes
exp(n)	exp(n), the function
acosh(f)	acoshf(f)
sin(d)	sin(d), the function
atan(ld)	atanl(ld)
log(fc)	clogf(fc)
sqrt(dc)	csqrt(dc)
pow(ldc,f)	cpowl(ldc, f)
remainder(n,n)	remainder(n, n), the function
nextafter(d,f)	nextafter(d, f), the function
nexttoward(f,ld)	nexttowardf(f, ld)
copysign(n,ld)	copysignl(n, ld)
ceil(fc)	undefined behavior
rint(dc)	undefined behavior
fmax(ldc,ld)	undefined behavior
carg(n)	carg(n), the function
cproj(f)	cprojf(f)
creal(d)	creal(d), the function
cimag(ld)	cimagl(ld)
cabs(fc)	cabsf(fc)
carg(dc)	carg(dc), the function
cproj(ldc)	cprojl(ldc)

Attributes

See attributes(5) for descriptions of the following attributes:

ATTRIBUTE TYPE	ATTRIBUTE VALUE
Interface Stability	Standard