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FEENABLEEXCEPT(3)	 BSD Library Functions Manual	     FEENABLEEXCEPT(3)

NAME
     feenableexcept, fedisableexcept, fegetexcept -- floating-point exception
     masking

LIBRARY
     Math Library (libm, -lm)

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

     int
     feenableexcept(int	excepts);

     int
     fedisableexcept(int excepts);

     int
     fegetexcept(void);

DESCRIPTION
     The feenableexcept() and fedisableexcept()	functions unmask and mask (re-
     spectively) exceptions specified in excepts.  The fegetexcept() function
     returns the current exception mask.  All exceptions are masked by de-
     fault.

     Floating-point operations that produce unmasked exceptions	will trap, and
     a SIGFPE will be delivered	to the process.	 By installing a signal	han-
     dler for SIGFPE, applications can take appropriate	action immediately
     without testing the exception flags after every operation.	 Note that the
     trap may not be immediate,	but it should occur before the next floating-
     point instruction is executed.

     For all of	these functions, the possible types of exceptions include
     those described in	fenv(3).  Some architectures may define	other types of
     floating-point exceptions.

RETURN VALUES
     The feenableexcept(), fedisableexcept(), and fegetexcept()	functions re-
     turn a bitmap of the exceptions that were unmasked	prior to the call.

SEE ALSO
     sigaction(2), feclearexcept(3), feholdexcept(3), fenv(3), feupdateenv(3)

BUGS
     Functions in the standard library may trigger exceptions multiple times
     as	a result of intermediate computations; however,	they generally do not
     trigger spurious exceptions.

     No	interface is provided to permit	exceptions to be handled in nontrivial
     ways.  There is no	uniform	way for	an exception handler to	access infor-
     mation about the exception-causing	instruction, or	to determine whether
     that instruction should be	reexecuted after returning from	the handler.

BSD				March 16, 2005				   BSD

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | RETURN VALUES | SEE ALSO | BUGS

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