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fwide(3p) — Linux manual page

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

PROLOG        top

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

NAME        top

       fwide — set stream orientation

SYNOPSIS        top

       #include <stdio.h>       #include <wchar.h>       int fwide(FILE *stream, intmode);

DESCRIPTION        top

       The functionality described on this reference page is aligned with       the ISO C standard. Any conflict between the requirements       described here and the ISO C standard is unintentional. This       volume of POSIX.1‐2017 defers to the ISO C standard.       Thefwide() function shall determine the orientation of the stream       pointed to bystream.  Ifmode is greater than zero, the function       first attempts to make the stream wide-oriented. Ifmode 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.       Thefwide() function shall not change the setting oferrno if       successful.       Since no return value is reserved to indicate an error, an       application wishing to check for error situations should seterrno       to 0, then callfwide(), then checkerrno, and if it is non-zero,       assume an error has occurred.

RETURN VALUE        top

       Thefwide() 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        top

       Thefwide() function may fail if:EBADFThestream argument is not a valid stream.The following sections are informative.

EXAMPLES        top

       None.

APPLICATION USAGE        top

       A call tofwide() withmode set to zero can be used to determine       the current orientation of a stream.

RATIONALE        top

       None.

FUTURE DIRECTIONS        top

       None.

SEE ALSO        top

       The Base Definitions volume of POSIX.1‐2017,stdio.h(0p),wchar.h(0p)

COPYRIGHT        top

       Portions of this text are reprinted and reproduced in electronic       form from IEEE Std 1003.1-2017, Standard for Information       Technology -- Portable Operating System Interface (POSIX), The       Open Group Base Specifications Issue 7, 2018 Edition, Copyright       (C) 2018 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 athttp://www.opengroup.org/unix/online.html .       Any typographical or formatting errors that appear in this page       are most likely to have been introduced during the conversion of       the source files to man page format. To report such errors, seehttps://www.kernel.org/doc/man-pages/reporting_bugs.html .IEEE/The Open Group                2017FWIDE(3P)

Pages that refer to this page:wchar.h(0p)

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