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.