FWIDE(3P)                                           POSIX Programmer's Manual                                          FWIDE(3P)



PROLOG
       This  manual  page is part of the POSIX Programmer's Manual.  The Linux implementation of this interface may differ (con-
       sult the corresponding Linux manual page for details of Linux behavior), or the  interface  may  not  be  implemented  on
       Linux.

NAME
       fwide - set stream orientation

SYNOPSIS
       #include <stdio.h>
       #include <wchar.h>

       int fwide(FILE *stream, int mode);


DESCRIPTION
       The  fwide()  function  shall determine the orientation of the stream pointed to by stream. If mode is greater than zero,
       the function first attempts to make the stream wide-oriented.  If mode is less than zero, the function first attempts  to
       make the stream byte-oriented. Otherwise, mode is zero and the function does not alter the orientation of the stream.

       If the orientation of the stream has already been determined, fwide() shall not change it.

       Since  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.

RETURN VALUE
       The fwide() function shall return a value greater than zero if, after the call, the stream has wide-orientation, a  value
       less than zero if the stream has byte-orientation, or zero if the stream has no orientation.

ERRORS
       The fwide() function may fail if:

       EBADF  The stream argument is not a valid stream.


       The following sections are informative.

EXAMPLES
       None.

APPLICATION USAGE
       A call to fwide() with mode set to zero can be used to determine the current orientation of a stream.

RATIONALE
       None.

FUTURE DIRECTIONS
       None.

SEE ALSO
       The Base Definitions volume of IEEE Std 1003.1-2001, <wchar.h>

COPYRIGHT
       Portions  of  this  text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Standard for
       Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6,  Copy-
       right (C) 2001-2003 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any
       discrepancy between this version 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.open-
       group.org/unix/online.html .



IEEE/The Open Group                                           2003                                                     FWIDE(3P)