1FETESTEXCEPT(3P)           POSIX Programmer's Manual          FETESTEXCEPT(3P)
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PROLOG

6       This  manual  page is part of the POSIX Programmer's Manual.  The Linux
7       implementation of this interface may differ (consult the  corresponding
8       Linux  manual page for details of Linux behavior), or the interface may
9       not be implemented on Linux.
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NAME

12       fetestexcept - test floating-point exception flags
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SYNOPSIS

15       #include <fenv.h>
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17       int fetestexcept(int excepts);
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DESCRIPTION

21       The fetestexcept() function shall determine which of a specified subset
22       of  the  floating-point  exception flags are currently set. The excepts
23       argument specifies the floating-point status flags to be queried.
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RETURN VALUE

26       The fetestexcept() function shall return  the  value  of  the  bitwise-
27       inclusive  OR  of  the floating-point exception macros corresponding to
28       the currently set floating-point exceptions included in excepts.
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ERRORS

31       No errors are defined.
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33       The following sections are informative.
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EXAMPLES

36       The following example calls function f() if  an  invalid  exception  is
37       set, and then function g() if an overflow exception is set:
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40              #include <fenv.h>
41              /* ... */
42              {
43                  #pragma STDC FENV_ACCESS ON
44                  int set_excepts;
45                  feclearexcept(FE_INVALID | FE_OVERFLOW);
46                  // maybe raise exceptions
47                  set_excepts = fetestexcept(FE_INVALID | FE_OVERFLOW);
48                  if (set_excepts & FE_INVALID) f();
49                  if (set_excepts & FE_OVERFLOW) g();
50                  /* ... */
51              }
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APPLICATION USAGE

54       None.
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RATIONALE

57       None.
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FUTURE DIRECTIONS

60       None.
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SEE ALSO

63       feclearexcept(),  fegetexceptflag(),  feraiseexcept(), the Base Defini‐
64       tions volume of IEEE Std 1003.1-2001, <fenv.h>
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67       Portions of this text are reprinted and reproduced in  electronic  form
68       from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
69       -- Portable Operating System Interface (POSIX),  The  Open  Group  Base
70       Specifications  Issue  6,  Copyright  (C) 2001-2003 by the Institute of
71       Electrical and Electronics Engineers, Inc and The Open  Group.  In  the
72       event of any discrepancy between this version and the original IEEE and
73       The Open Group Standard, the original IEEE and The Open Group  Standard
74       is  the  referee document. The original Standard can be obtained online
75       at http://www.opengroup.org/unix/online.html .
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79IEEE/The Open Group                  2003                     FETESTEXCEPT(3P)
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