.\"
.\" Copyright (c) 1996 SigmaSoft, Th. Lockert
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.\"	$OpenBSD: update.8,v 1.4 1996/07/13 22:45:25 millert Exp $
.\"
.Dd June 8, 1996
.Dt UPDATE 8
.Os
.Sh NAME
.Nm update
.Nd flush internal filesystem caches to disk frequently
.Sh SYNOPSIS
.Nm update
.Sh DESCRIPTION
The
.Nm update
command no longer exists, but has been incorporated into
the kernel where it will flush dirty buffers that have not
been touched for thirty seconds or more.
.Pp
The same effect can be seen by using the
.Xr sync 8
command, although the in-kernel
.Nm update
process will do this in a staggered manner.
.Sh SEE ALSO
.Xr sync 2 ,
.Xr fsck 8 ,
.Xr init 8 ,
.Xr sync 8
.Sh BUGS
It is possible on some systems, that a
.Xr sync
occuring simultaneously with a crash may cause
file system damage. See
.Xr fsck 8 .
.Sh HISTORY
An
.Nm update
command appeared in
.At v6 .
.Pp
The
.Nm update
command was incorporated into the kernel in
.Ox 1.2 .