DragonFly On-Line Manual Pages

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SYNC(2) DragonFly 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)
HISTORY
 A sync() function call appeared in Version 6 AT&T UNIX.
BUGS
 Sync() may return before the buffers are completely flushed.
DragonFly 3.5 June 4, 1993 DragonFly 3.5

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