fsync(S)
fsync --
synchronize a file's in-memory state with that on the physical medium
Synopsis
#include <unistd.h>
int fsync(int fildes);
Description
fsync moves all modified data and attributes of fildes
to a storage device.
When fsync returns,
all in-memory modified copies
of buffers associated with fildes
have been written to the physical medium.
fsync is different from
sync,
which schedules disk I/O for all files
but returns before the I/O completes.
Return values
On success, fsync returns 0.
On failure, fsync returns -1 and sets errno to identify the error.
Errors
In the following conditions, fsync fails and sets errno to:
EBADF-
fildes is not a valid file descriptor open for writing.
ENOLINK-
fildes is on a remote machine and the link on that machine is
no longer active.
EINTR-
A signal was caught during execution of the fsync system call.
EIO-
An I/O error occurred while reading from or writing to the file system.
Usage
fsync
should be used by programs that require that a file be
in a known state.
For example, a program that contains
a simple transaction facility might use fsync to ensure that all
changes to a file or files caused by a given transaction were
recorded on a storage medium.
References
sync(S)
Notices
The way the data reach the physical medium
depends on both implementation and hardware.
fsync returns when the device
driver tells it that the write has taken place.
© 2005 The SCO Group, Inc. All rights reserved.
SCO OpenServer Release 6.0.0 - 01 June 2005