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TGMATH(3)                  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(3)             cacos(3)
           asin()              asin(3)             casin(3)
           atan()              atan(3)             catan(3)
           acosh()             acosh(3)            cacosh(3)
           asinh()             asinh(3)            casinh(3)
           atanh()             atanh(3)            catanh(3)
           cos()               cos(3)              ccos(3)
           sin()               sin(3)              csin(3)
           tan()               tan(3)              ctan(3)
           cosh()              cosh(3)             ccosh(3)
           sinh()              sinh(3)             csinh(3)
           tanh()              tanh(3)             ctanh(3)
           exp()               exp(3)              cexp(3)
           log()               log(3)              clog(3)
           pow()               pow(3)              cpow(3)
           sqrt()              sqrt(3)             csqrt(3)
           fabs()              fabs(3)             cabs(3)

     No complex functions exist for the following macros, so passing a complex
     value to a generic argument invokes undefined behaviour:

           atan2(3)          fma()             llround()         remainder(3)
           cbrt(3)           fmax(3)           log10(3)          remquo()
           ceil(3)           fmin(3)           log1p(3)          rint(3)
           copysign(3)       fmod(3)           log2(3)           round(3)
           erf(3)            frexp(3)          logb(3)           scalbn(3)
           erfc(3)           hypot(3)          lrint(3)          tgamma()
           exp2(3)           ilogb(3)          lround()          trunc(3)
           expm1(3)          ldexp(3)          nextafter(3)
           fdim(3)           lgamma(3)
           floor(3)          llrint(3)

     The following macros always expand to a complex function:

           carg(3)     cimag(3)    conj(3)     cproj()     creal(3)

     This header includes <complex.h> and <math.h>.

STANDARDS
     The header <tgmath.h> conforms to ISO/IEC 9899:1999 ("ISO C99").

AUTHORS
     Matt Thomas <matt@3am-software.com>

BUGS
     The header <tgmath.h> cannot be implemented with strictly conforming C
     code and needs special compiler support.  The current implementation only
     works for GCC.

     Many of the functions mentioned here are not prototyped in <math.h> or
     <complex.h> as they are not yet implemented.

NetBSD 10.99                   December 14, 2010                  NetBSD 10.99