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TGMATH(3) DragonFly Library Functions Manual TGMATH(3)
NAME
tgmath -- type-generic macros
SYNOPSIS
#include <tgmath.h>
DESCRIPTION
The header <tgmath.h> provides type-generic macros for <math.h> and
<complex.h> functions that have float (suffixed with f), double and long
double (suffixed with l) versions. The arguments that vary across the
three functions and have type float, double and long double,
respectively, are called generic arguments.
The following rules describe which function is actually called if a type-
generic macro is invoked. If any generic argument has type long double
or long double complex, the long double function is called. Else, if any
generic argument has type double, double complex or an integer type, the
double version is invoked. Otherwise, the macro expands to the float
implementation.
For the macros in the following table, both real and complex functions
exist. The real functions are prototyped in <math.h> and the complex
equivalents in <complex.h>. The complex function is called if any of the
generic arguments is a complex value. Otherwise, the real equivalent is
called.
Macro real function complex function
acos() acos() cacos()
asin() asin() casin()
atan() atan() catan()
acosh() acosh() cacosh()
asinh() asinh() casinh()
atanh() atanh() catanh()
cos() cos() ccos()
sin() sin() csin()
tan() tan() ctan()
cosh() cosh() ccosh()
sinh() sinh() csinh()
tanh() tanh() ctanh()
exp() exp() cexp()
log() log() clog()
pow() pow() cpow()
sqrt() sqrt() csqrt()
fabs() fabs() cabs()
No complex functions exist for the following macros, so passing a complex
value to a generic argument invokes undefined behaviour:
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()
The following macros always expand to a complex function:
carg() cimag() conj() cproj() creal()
This header includes <complex.h> and <math.h>.
STANDARDS
The header <tgmath.h> conforms to ISO/IEC 9899:1999 (``ISO C99'').
HISTORY
The header <tgmath.h> first appeared in FreeBSD 5.3.
COMPILER SUPPORT
Before ISO/IEC 9899:2011 (``ISO C11''), the header <tgmath.h> could not
be implemented with strictly conforming C code and needed special
compiler support. As of ISO/IEC 9899:2011 (``ISO C11''), this header
file can be implemented using the _Generic() language keyword. In
addition to compilers that support this keyword, this header file works
with GCC.
BUGS
Many of the functions mentioned here are not prototyped in <math.h> or
<complex.h> as they are not yet implemented. This prevents the
corresponding type-generic macro from working at all.
DragonFly 4.3 June 2, 2013 DragonFly 4.3