.TH UP 1 
.SH NAME
up \- update a tree
.SH SYNOPSIS
.B up
[
.B -cugst
]
.I src
.I dst
.SH DESCRIPTION
.I Up
prints shell commands needed to make
.I dst
like
.IR src .
Both arguments may name files or directories and exist or not
exist.
.PP
By default, user and group ids are ignored. Flag
.B -u
makes the user and group ids to be considered.
Flag
.B -g
makes group ids to be considered.
.PP
Flag
.B -c
makes
.I up
report changes instead of commands to update the
destination file. Each change is indicated by the initial of
.IR added ,
.IR deleted ,
.IR mode-changed ,
and
.IR changed
followed by the file name, relative to the destination directory.
.PP
Flag
.B -s
makes the tool silent, reporting through
the exit status non-nil only if
.I src
and
.I dst
differ. 
.PP
Flag
.B -t
relies on the file length and modification time to guess if two
files are the same or differ. Under this flag, no update is reported
for files that exist both in the destination and the origin and are
newer in the destination.
.SH SOURCE
.B /sys/src/cmd/up.c
.SH EXAMPLE
.EX
; up /rc/bin/patch /n/src/nix/rc/bin/patch
chmod 0775 /n/src/nix/rc/bin/patch/applied
fcp -x /rc/bin/patch/apply /n/src/nix/rc/bin/patch/apply
chmod 0775 /n/src/nix/rc/bin/patch/create
chmod 0775 /n/src/nix/rc/bin/patch/okay
chmod 0775 /n/src/nix/rc/bin/patch/undo
.EE