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 characters. 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 infor- mation.
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
Mac OS X 10.6 - Generated Thu Sep 17 20:23:27 CDT 2009