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UNGETWC(3)                 Library Functions Manual                 UNGETWC(3)

NAME
     ungetwc - 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);

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 by subsequent reads on the stream
     (in reverse order).  A successful intervening call, using the same
     stream, to one of the file positioning functions fseek(3), fsetpos(3), or
     rewind(3) will discard the pushed back wide characters.

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

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

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)

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

BUGS
     The current implementation uses a fixed sized ungetwc-buffer.

NetBSD 10.99                   October 24, 2001                   NetBSD 10.99