Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages

  
 
  

home | help
SYNC(2)			    BSD	System Calls Manual		       SYNC(2)

NAME
     sync -- synchronize disk block in-core status with	that on	disk

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 update(4) (about every 30 seconds).

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

SEE ALSO
     fsync(2), update(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.

4th Berkeley Distribution	 June 4, 1993	     4th Berkeley Distribution

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

Want to link to this manual page? Use this URL:
<https://www.freebsd.org/cgi/man.cgi?query=sync&sektion=2&manpath=FreeBSD+3.2-RELEASE>

home | help