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UNGETWC(3)               BSD Library Functions Manual               UNGETWC(3)

NAME
     ungetwc, ungetwc_l -- un-get wide character from input stream

LIBRARY
     Standard C Library (libc, -lc)

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

     wint_t
     ungetwc(wint_t wc, FILE *stream);

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

     wint_t
     ungetwc_l(wint_t wc, FILE *stream, locale_t loc);

DESCRIPTION
     The ungetwc() function pushes the wide character wc (converted to an wchar_t) back onto the input
     stream pointed to by stream.  The pushed-backed wide characters will be returned (in reverse order) by
     subsequent reads on the stream.  A successful intervening call to one of the file positioning functions
     fseek(3), fsetpos(3), or rewind(3), using the same stream, will discard the pushed-back wide charac-ters. characters.
     ters.

     Only one wide character of push-back is guaranteed, but as long as there is sufficient memory, an
     effectively infinite amount of push-back is allowed.

     If a character is successfully pushed-back, the end-of-file indicator for the stream is cleared.

     Although the ungetwc() function uses the current locale, the ungetwc_l() function may be passed a
     locale directly. See xlocale(3) for more information.

RETURN VALUES
     The ungetwc() function returns the wide character pushed-back after the conversion, or WEOF if the
     operation fails.  If the value of the argument c character equals WEOF, the operation will fail and the
     stream will remain unchanged.

SEE ALSO
     fseek(3), getwc(3), xlocale(3)

STANDARDS
     The ungetwc() function conforms to ISO/IEC 9899:1999 (``ISO C99'').

BSD                              March 3, 2004                             BSD