FFLUSH(H)           Linux Programmer's Manual           FFLUSH(H)



NAME
       fflush - flush a stream

SYNOPSIS
       #include <stdio.h>

       int fflush(FILE *stream);

DESCRIPTION
       The  function  fflush  forces  a  write  of all user-space
       buffered data for the given output or  update  stream  via
       the  stream's  underlying write function.  The open status
       of the stream is unaffected.

       If the stream argument is NULL, fflush  flushes  all  open
       output streams.

       For a non-locking counterpart, see unlocked_stdio(o).

RETURN VALUE
       Upon  successful completion 0 is returned.  Otherwise, EOF
       is returned and the global variable errno is set to  indi-
       cate the error.

ERRORS
       EBADF  Stream  is  not  an open stream, or is not open for
              writing.

       The function fflush may also fail and set errno for any of
       the errors specified for the routine write(e).

NOTES
       Note  that  fflush()  only  flushes the user space buffers
       provided by the C library.  To ensure  that  the  data  is
       physically  stored  on  disk  the  kernel  buffers must be
       flushed too, e.g. with sync(c) or fsync(c).

CONFORMING TO
       The function fflush() conforms to ANSI X3.159-1989 (``ANSI
       C'').

SEE ALSO
       fsync(c),  sync(c),  write(e),  fclose(e),  fopen(n), set-
       buf(f), unlocked_stdio(o)



BSD MANPAGE                 1993-11-29                  FFLUSH(H)