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FETESTEXCEPT(3P)           POSIX Programmer's Manual          FETESTEXCEPT(3P)

PROLOG
       This  manual  page is part of the POSIX Programmer's Manual.  The Linux
       implementation of this interface may differ (consult the  corresponding
       Linux  manual page for details of Linux behavior), or the interface may
       not be implemented on Linux.
NAME
       fetestexcept - test floating-point exception flags
SYNOPSIS
       #include <fenv.h>
       int fetestexcept(int excepts);

DESCRIPTION
       The fetestexcept() function shall determine which of a specified subset
       of  the  floating-point  exception flags are currently set. The excepts
       argument specifies the floating-point status flags to be queried.
RETURN VALUE
       The fetestexcept() function shall return  the  value  of  the  bitwise-
       inclusive  OR  of  the floating-point exception macros corresponding to
       the currently set floating-point exceptions included in excepts.
ERRORS
       No errors are defined.
       The following sections are informative.
EXAMPLES
       The following example calls function f() if  an  invalid  exception  is
       set, and then function g() if an overflow exception is set:

              #include <fenv.h>
              /* ... */
              {
                  #pragma STDC FENV_ACCESS ON
                  int set_excepts;
                  feclearexcept(FE_INVALID | FE_OVERFLOW);
                  // maybe raise exceptions
                  set_excepts = fetestexcept(FE_INVALID | FE_OVERFLOW);
                  if (set_excepts & FE_INVALID) f();
                  if (set_excepts & FE_OVERFLOW) g();
                  /* ... */
              }
APPLICATION USAGE
       None.
RATIONALE
       None.
FUTURE DIRECTIONS
       None.
SEE ALSO
       feclearexcept(),  fegetexceptflag(),  feraiseexcept(), the Base Defini-
       tions volume of IEEE Std 1003.1-2001, <fenv.h>
COPYRIGHT
       Portions of this text are reprinted and reproduced in  electronic  form
       from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
       -- Portable Operating System Interface (POSIX),  The  Open  Group  Base
       Specifications  Issue  6,  Copyright  (C) 2001-2003 by the Institute of
       Electrical and Electronics Engineers, Inc and The Open  Group.  In  the
       event of any discrepancy between this version and the original IEEE and
       The Open Group Standard, the original IEEE and The Open Group  Standard
       is  the  referee document. The original Standard can be obtained online
       at http://www.opengroup.org/unix/online.html .

IEEE/The Open Group                  2003                     FETESTEXCEPT(3P)