system_cmds-735.20.1.tar.gz

[apple/system_cmds.git] / sync.tproj / sync.8

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.\"	@(#)sync.8	8.1 (Berkeley) 5/31/93
.\" $FreeBSD: src/bin/sync/sync.8,v 1.16 2005/01/10 08:39:26 imp Exp $
.\"
.Dd May 31, 1993
.Dt SYNC 8
.Os
.Sh NAME
.Nm sync
.Nd force completion of pending disk writes (flush cache)
.Sh SYNOPSIS
.Nm
.Sh DESCRIPTION
The
.Nm
utility
can be called to ensure that all disk writes have been completed before the
processor is halted in a way not suitably done by
.Xr shutdown 8 .
Generally, it is preferable to use
.Xr shutdown 8
to shut down the system,
as they may perform additional actions
such as resynchronizing the hardware clock
and flushing internal caches before performing a final
.Nm .
.Pp
The
.Nm
utility utilizes the
.Xr sync 2
function call.
.Sh SEE ALSO
.Xr fsync 2 ,
.Xr sync 2 ,
.Xr shutdown 8
.Sh HISTORY
A
.Nm
utility appeared in
.At v4 .