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 SunOS 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]
Copyright (c) 1992, X/Open Company Limited. All Rights Reserved.
Portions Copyright (c) 2002, Sun Microsystems, Inc. All Rights Reserved
#include <stdio.h> #include <wchar.h> int fwide(FILE *stream, int mode);
The fwide() function determines the orientation of the stream pointed to by stream. If mode is greater than 0, the function first attempts to make the stream wide-oriented. If mode is less than 0, the function first attempts to make the stream byte-oriented. Otherwise, mode is 0 and the function does not alter the orientation of the stream.
If the orientation of the stream has already been determined, fwide() does not change it.
Because no return value is reserved to indicate an error, an application wishing to check for error situations should set errno to 0, then call fwide(), then check errno and if it is non-zero, assume an error has occurred.
The fwide() function returns a value greater than 0 if, after the call, the stream has wide-orientation, a value less than 0 if the stream has byte-orientation, or 0 if the stream has no orientation.
The fwide() function may fail if: EBADF
The stream argument is not a valid stream.
A call to fwide() with mode set to 0 can be used to determine the current orientation of a stream.
See attributes(7) for descriptions of the following attributes:
| ATTRIBUTE TYPE ATTRIBUTE VALUE |
| Interface Stability Standard |
| MT-Level MT-Safe |
attributes (7), standards (7)