ungetwc

UNGETWC(3)                 Linux Programmer's Manual                UNGETWC(3)



NAME
       ungetwc - push back a wide character onto a FILE stream

SYNOPSIS
       #include <wchar.h>

       wint_t ungetwc(wint_t wc, FILE *stream);

DESCRIPTION
       The  ungetwc  function  is  the wide-character equivalent of the ungetc
       function. It pushes back a wide character onto stream and returns it.

       If wc is WEOF, it returns WEOF. If wc is an invalid wide character,  it
       sets errno to EILSEQ and returns WEOF.

       If  wc is a valid wide character, it is pushed back onto the stream and
       thus becomes available for future wide character read operations.   The
       file-position  indicator is decremented by one or more. The end-of-file
       indicator is cleared. The backing storage of the file is not  affected.

       Note:  wc  need not be the last wide character read from the stream; it
       can be any other valid wide character.

       If the implementation supports multiple push-back operations in a  row,
       the pushed-back wide characters will be read in reverse order; however,
       only one level of push-back is guaranteed.

RETURN VALUE
       The ungetwc function returns wc when successful, or WEOF upon  failure.

CONFORMING TO
       ISO/ANSI C, UNIX98

SEE ALSO
       fgetwc(3)

NOTES
       The  behaviour  of ungetwc depends on the LC_CTYPE category of the cur-
       rent locale.



GNU                               1999-09-19                        UNGETWC(3)