fflush(3)


NAME

   fflush - flush a stream

SYNOPSIS

   #include <stdio.h>

   int fflush(FILE *stream);

DESCRIPTION

   For  output streams, fflush() forces a write of all user-space buffered
   data for the given output or update stream via the stream's  underlying
   write function.

   For input streams associated with seekable files (e.g., disk files, but
   not pipes or terminals), fflush() discards any buffered data  that  has
   been fetched from the underlying file, but has not been consumed by the
   application.

   The open status of the stream is unaffected.

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

   For a nonlocking counterpart, see unlocked_stdio(3).

RETURN VALUE

   Upon  successful  completion 0 is returned.  Otherwise, EOF is returned
   and 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 write(2).

ATTRIBUTES

   For   an   explanation   of   the  terms  used  in  this  section,  see
   attributes(7).

   
   Interface  Attribute      Value   
   
   fflush()   Thread safety  MT-Safe 
   

CONFORMING TO

   C89, C99, POSIX.1-2001, POSIX.1-2008.

   POSIX.1-2001 did  not  specify  the  behavior  for  flushing  of  input
   streams, but the behavior is specified in POSIX.1-2008.

NOTES

   Note  that fflush() flushes only 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), fileno(3), fopen(3), setbuf(3),
   unlocked_stdio(3)

COLOPHON

   This  page  is  part of release 4.09 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
   https://www.kernel.org/doc/man-pages/.


More Linux Commands

manpages/trunc.3.html
trunc(3) - round to integer, toward zero - Linux man page...
These functions round x to the nearest integer not larger in absolute value. RETURN VALUE These functions return the rounded integer value. If x is integral, in

manpages/svnmucc.1.html
svnmucc(1) Multiple URL Command Client for Subversion.......
svnmucc.1 - Subversion is a version control system, which allows you to keep old versions of files and directories (usually source code), keep a log of who, whe

manpages/SDL_GetMouseState.3.html
SDL_GetMouseState(3) - Retrieve the current state of the mou
The current button state is returned as a button bitmask, which can be tested using the SDL_BUTTON(X) macros, and x and y are set to the current mouse cursor po

manpages/wineboot.1.html
wineboot(1) - perform Wine initialization, startup, and shut
wineboot performs the initial creation and setup of a WINEPREFIX for wine(1). It can also perform a simulated reboot or shutdown to any applications running wit

manpages/getresuid.2.html
getresuid(2) - get real, effective and saved user/group IDs
getresuid() returns the real UID, the effective UID, and the saved set-user-ID of the calling process, in the arguments ruid, euid, and suid, respectively. getr

manpages/grub2-mknetdir.1.html
grub2-mknetdir(1) prepare a GRUB netboot directory..........
--compress[=no,xz,gz,lzo] compress GRUB files [optional] -d, --directory=DIR use images and modules under DIR [default=/usr/lib/grub2/&lt;platform&gt;] --fonts=FONTS

manpages/gnutls_pkcs11_token_set_pin.3.html
gnutls_pkcs11_token_set_pin(3) - API function (Man Page)....
This function will modify or set a users PIN for the given token. If it is called to set a user pin for first time the oldpin must be NULL. RETURNS On success,

manpages/startproc.8.html
startproc(8) - Start processes identified by path name......
startproc and the LSB variant start_daemon check for all processes of the specified executable and starts it if no processes are found. Note that startproc is d

manpages/Module::Build::Platform::VOS.3pm.html
Module::Build::Platform::VOS(3pm) - Builder class for VOS pl
Module::Build::Platform::VOS.3pm - The sole purpose of this module is to inherit from Module::Build::Base. Please see the Module::Build for the docs. AUTHOR Ken

manpages/git-cat-file.1.html
git-cat-file(1) - Provide content or type and size informati
In its first form, the command provides the content or the type of an object in the repository. The type is required unless -t or -p is used to find the object

manpages/index.1.html
index(1) - netpbm library overview - Linux manual page......
Netpbm is a package of graphics programs and a programming library. There are over 220 separate programs in the package, most of which have pbm, pgm, ......

manpages/spufs.7.html
spufs(7) - SPU file system (Miscellaneous - Linux man page)
The SPU filesystem is used on PowerPC machines that implement the Cell Broadband Engine Architecture in order to access Synergistic Processor Units (SPUs). The





We can't live, work or learn in freedom unless the software we use is free.