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FEGETENV(3)              BSD Library Functions Manual              FEGETENV(3)

NAME
     fegetenv, feholdexcept, fesetenv, feupdateenv -- functions providing access to the floating-point envi-ronment. environment.
     ronment.

SYNOPSIS
     #include <fenv.h>
     #pragma STDC FENV_ACCESS ON

     int
     fegetenv(fenv_t *envp);

     int
     feholdexcept(fenvt_t *envp);

     int
     fesetenv(fenv_t *envp);

     int
     feupdateenv(fenv_t *envp);

DESCRIPTION
     These functions provide the means to manage the entire floating-point environment--including both sta-tus status
     tus flags and control modes--as a single entity.

     The fegetenv() function attempts to store the current floating-point environment in the object pointed
     to by envp.  It returns zero if the environment was successfully stored, and a nonzero value otherwise.

     The feholdexcept() function saves the current floating-point environment in the object pointed to by
     envp, clears the floating-point status flags, and then installs a "non-stop" mode, if available, under
     which no traps are taken for floating-point exceptions (as is the case in default IEEE-754 floating-point floatingpoint
     point execution).  It returns zero if and only if such a mode was successfully installed.

     The fesetenv() function attempts to establish the floating-point environment represented by the object
     pointed to by envp.  This object shall have been set by a call to fegetenv() or feholdexcept(), or be
     equal to a floating-point environment macro defined in <fenv.h>.  Note that this function merely
     installs the floating-point status flags represented by its argument, and does not raise the corre-sponding corresponding
     sponding floating-point exceptions.  It returns zero if and only if the environment pointed to by envp
     was successfully installed.

     The feupdateenv() function attempts to save the currently raised floating-point flags, install the
     floating-point environment represented by *envp, and then raise the floating-point exceptions corre-sponding corresponding
     sponding to the saved flags.  The object pointed to by envp shall have been set by a call to fegetenv()
     or feholdexcept(), or be equal to a floating-point environment macro defined in <fenv.h>.  It returns
     zero if and only if all of the specified actions were successfully carried out.

SEE ALSO
     fenv(3), feclearexcept(3), fegetexceptflag(3), fegetround(3), feraiseexcept(3), fesetexceptflag(3),
     fesetround(3), feraiseexcept(3)

STANDARDS
     These functions conform to ISO/IEC 9899:TC3.

BSD                               May 9, 2011                              BSD