SYNC(2) 		  FreeBSD System Calls Manual		       SYNC(2)

NAME
     sync - schedule filesystem updates

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <unistd.h>

     void
     sync(void);

DESCRIPTION
     The sync() function 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() call is
     issued frequently by the user process syncer(4) (about every 30 seconds).

     The function fsync(2) may be used to synchronize individual file descrip-
     tor attributes.

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

BUGS
     Sync() may return before the buffers are completely flushed.

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

FreeBSD 4.8			 June 4, 1993			   FreeBSD 4.8