NAME
ungetwc —
un-get wide character from input
stream
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 a
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
STANDARDS
The ungetwc() function conforms to
ISO/IEC 9899:1999
(“ISO C99”).
BUGS
The current implementation uses a fixed sized ungetwc-buffer.