minix/man/man3/feholdexcept.3

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2009-12-24 21:22:41 +01:00
.TH FEHOLDEXCEPT 3 "December 22, 2009"
.UC 4
.SH NAME
feholdexcept \- disable floating point exceptions
.SH SYNOPSIS
.nf
.ft B
#include <fenv.h>
int feholdexcept(fenv_t *\fIenvp\fP);
.fi
.SH DESCRIPTION
The feholdexcept function disables floating point exceptions. The floating
point environment prior to disabling exceptions is stored in the struct
pointed to by \fIenvp\fP.
.SH "RETURN VALUE"
On x86, this function never fails and the return value is always 0. A portable
program should, however, consider the possibility that this function may fail
and will return -1 to indicate this.
.SH "KNOWN ISSUES"
POSIX requires the function to clear exception flags. However, as none of the
other functions dealing with FPU flags and FPU state have been implemented this
has no effect on MINIX. A full implementation may need to store more FPU state
as there is no instruction to change the status word independent of the rest
of the FPU state. Do not depend on the fields of fenv_t as they may change even
on future versions of MINIX/x86.