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 current locale.