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SYNC(2)			    BSD	System Calls Manual		       SYNC(2)

NAME
     sync -- schedule file system updates

LIBRARY
     Standard C	Library	(libc, -lc)

SYNOPSIS
     #include <unistd.h>

     void
     sync(void);

DESCRIPTION
     The sync()	system call forces a write of dirty (modified) buffers in the
     block buffer cache	out to disk.  The kernel keeps this information	in
     core to reduce the	number of disk I/O transfers required by the system.
     As	information in the cache is lost after a system	crash, a sync()	system
     call is issued frequently by the user process syncer(4) (about every 30
     seconds).

     The fsync(2) system call may be used to synchronize individual file de-
     scriptor attributes.

SEE ALSO
     fsync(2), syncer(4), sync(8)

BUGS
     The sync()	system call may	return before the buffers are completely
     flushed.

HISTORY
     The sync()	function appeared in Version 6 AT&T UNIX.

BSD				 June 4, 1993				   BSD

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | SEE ALSO | BUGS | HISTORY

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