.\" Copyright (c) 1980 Regents of the University of California.
.\" All rights reserved.  The Berkeley software License Agreement
.\" specifies the terms and conditions for redistribution.
.\"
.\"	@(#)sync.2	6.2 (Berkeley) 6/30/85
.\"
.TH SYNC 2 "June 30, 1985"
.UC 4
.SH NAME
sync \- update super-block
.SH SYNOPSIS
.B sync()
.SH DESCRIPTION
.I Sync
causes all information in core
memory that should be on disk to be written out.
This includes modified super blocks,
modified i-nodes, and delayed block I/O.
.PP
.I Sync
should be used by programs that examine a file system,
for example
.I "fsck, df,"
etc.
.I Sync
is mandatory before a boot.
.SH "SEE ALSO"
fsync(2), sync(8), update(8)
.SH BUGS
The writing, although scheduled, is not necessarily
complete upon return from 
.IR sync .