unixdev.net


Switch to SpeakEasy.net DSL

The Modular Manual Browser

Home Page
Manual: (Debian-5.0)
Page:
Section:
Apropos / Subsearch:
optional field

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



NAME
       fflush - flush a stream

SYNOPSIS
       #include <&lt;stdio.h>&gt;

       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(3).

RETURN VALUE
       Upon successful completion 0 is returned.  Otherwise, EOF  is  returned
       and the global variable errno is set to indicate 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(2).

CONFORMING TO
       C89, C99.

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,  for  example,  with  sync(2)  or
       fsync(2).

SEE ALSO
       fsync(2),    sync(2),   write(2),   fclose(3),   fopen(3),   setbuf(3),
       unlocked_stdio(3)

COLOPHON
       This page is part of release 3.05 of the Linux  man-pages  project.   A
       description  of  the project, and information about reporting bugs, can
       be found at http://www.kernel.org/doc/man-pages/.



GNU                               1993-11-29                         FFLUSH(3)