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'\" te
.\" Copyright (c) 2001, the Institute of Electrical and Electronics Engineers, Inc. and The Open Group. All Rights Reserved.
.\" Portions Copyright (c) 2006, Sun Microsystems, Inc. All Rights Reserved.
.\" Sun Microsystems, Inc. gratefully acknowledges The Open Group for permission to reproduce portions of its copyrighted documentation. Original documentation from The Open Group can be obtained online at
.\" http://www.opengroup.org/bookstore/.
.\" The Institute of Electrical and Electronics Engineers and The Open Group, have given us permission to reprint portions of their documentation. In the following statement, the phrase "this text" refers to portions of the system documentation. Portions of this text are reprinted and reproduced in electronic form in the Sun OS Reference Manual, from IEEE Std 1003.1, 2004 Edition, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2004 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between these versions 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.
.\" This notice shall appear on any product containing this material.
.\" The contents of this file are subject to the terms of the Common Development and Distribution License (the "License"). You may not use this file except in compliance with the License.
.\" You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE or http://www.opensolaris.org/os/licensing. See the License for the specific language governing permissions and limitations under the License.
.\" When distributing Covered Code, include this CDDL HEADER in each file and include the License file at usr/src/OPENSOLARIS.LICENSE. If applicable, add the following below this CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your own identifying information: Portions Copyright [yyyy] [name of copyright owner]
.TH FEGETENV 3M "Jul 12, 2006" "SunOS 5.11" "Mathematical Library Functions"
.SH NAME
fegetenv, fesetenv \- get and set current floating-point environment
.SH SYNOPSIS
.LP
.nf
c99 [ \fIflag\fR... ] \fIfile\fR... \fB-lm\fR [ \fIlibrary\fR... ]
#include <fenv.h>
\fBint\fR \fBfegetenv\fR(\fBfenv_t *\fR\fIenvp\fR);
.fi
.LP
.nf
\fBint\fR \fBfesetenv\fR(\fBconst fenv_t *\fR\fIenvp\fR);
.fi
.SH DESCRIPTION
.sp
.LP
The \fBfegetenv()\fR function attempts to store the current floating-point
environment in the object pointed to by \fIenvp\fR.
.sp
.LP
The \fBfesetenv()\fR function attempts to establish the floating-point
environment represented by the object pointed to by \fIenvp\fR. The \fIenvp\fR
argument points to an object set by a call to \fBfegetenv()\fR or
\fBfeholdexcept\fR(3M), or equals a floating-point environment macro. The
\fBfesetenv()\fR function does not raise floating-point exceptions, but only
installs the state of the floating-point status flags represented through its
argument.
.SH RETURN VALUES
.sp
.LP
If the representation was successfully stored, fegetenv returns 0. Otherwise,
it returns a non-zero value.
.sp
.LP
If the environment was successfully established, fesetenv returns 0. Otherwise,
it returns a non-zero value.
.SH ERRORS
.sp
.LP
No errors are defined.
.SH ATTRIBUTES
.sp
.LP
See \fBattributes\fR(5) for descriptions of the following attributes:
.sp
.sp
.TS
tab( ) box;
cw(2.75i) |cw(2.75i)
lw(2.75i) |lw(2.75i)
.
ATTRIBUTE TYPE ATTRIBUTE VALUE
_
Interface Stability Standard
_
MT-Level MT-Safe
.TE
.SH SEE ALSO
.sp
.LP
\fBfeholdexcept\fR(3M), \fBfenv.h\fR(3HEAD), \fBfeupdateenv\fR(3M),
\fBattributes\fR(5), \fBstandards\fR(5)
.SH NOTES
.sp
.LP
In a multithreaded program, the \fBfegetenv()\fR and \fBfegetenv()\fR functions
affect the floating point environment only for the calling thread.
.sp
.LP
These functions automatically install and deinstall \fBSIGFPE\fR handlers and
set and clear the trap enable mode bits in the floating point status register
as needed. If a program uses these functions and attempts to install a
\fBSIGFPE\fR handler or control the trap enable mode bits independently, the
resulting behavior is not defined.
.sp
.LP
As described in \fBfex_set_handling\fR(3M)\fB\fR, when a handling function
installed in \fBFEX_CUSTOM\fR mode is invoked, all exception traps are disabled
(and will not be reenabled while \fBSIGFPE\fR is blocked). Thus, attempting to
change the environment from within a handler by calling \fBfesetenv\fR or
\fBfeupdateenv\fR(3M) might not produce the expected results.
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