Updated: 2021/Apr/14

TGMATH(3)                  Library Functions Manual                  TGMATH(3)

     tgmath - type-generic macros

     #include <tgmath.h>

     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

     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

           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>.

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

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

     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 9.99                    December 14, 2010                   NetBSD 9.99