fsync(2)							System Calls Manual							  fsync(2)

NAME

       fsync, fdatasync - synchronize a file's in-core and on-disk states

SYNOPSIS

DESCRIPTION

       and cause all modified data and attributes of fildes to be moved to a permanent storage device.	This normally results in all in-core modi-
       fied copies of buffers for the associated file to be written to a disk.	and apply to ordinary files, and apply to block special devices on
       systems which permit I/O to block special devices.

       and should be used by programs that require a file to be in a known state, such as when building a simple transaction facility.

       causes all modified data and file attributes of fildes required to retrieve the data to be written to disk.

       causes  all modified data and all file attributes of fildes (including access time, modification time and status change time) to be written
       to disk.

       Together, and constitute support for File Synchronization.

RETURN VALUE

       and return 0 on success or -1 if an error occurs, and set to indicate the error.

ERRORS

       fsync and fdatasync fail if any of the following conditions are encountered:

	      [EBADF]	     fildes is not a valid descriptor.

	      [EINVAL]	     fildes refers to a file type to which or does not apply.

WARNINGS

       The current implementation of these functions is inefficient for large files.

AUTHOR

       was developed by the University of California, Berkeley and HP.

SEE ALSO

       fcntl(2), fcntl(5), open(2), select(2), sync(2), sync(1M), unistd(5).

STANDARDS CONFORMANCE

																	  fsync(2)