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(3) 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 avail‐
       able for future wide-character read operations.  The  file-position  indicator  is  decre‐
       mented  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.

ATTRIBUTES
   Multithreading (see pthreads(7))
       The ungetwc() function is thread-safe.

CONFORMING TO
       C99.

NOTES
       The behavior of ungetwc() depends on the LC_CTYPE category of the current locale.

SEE ALSO
       fgetwc(3)

COLOPHON
       This  page  is  part of release 3.74 of the Linux man-pages project.  A description of the
       project, information about reporting bugs, and the latest version of  this  page,  can  be
       found at http://www.kernel.org/doc/man-pages/.



GNU                                         2013-12-09                                 UNGETWC(3)