Sprite 1984 - 1993/Sprite 1984 - 1993.iso/man/cmds/update.man

Text File | 1992-12-17 | 8KB | 180 lines

' $Header: /sprite/src/cmds/update/RCS/update.man,v 1.9 92/12/17 14:38:20 jhh Exp $ SPRITE (Berkeley)
.so \*(]ltmac.sprite
.HS UPDATE cmds
.BS
.SH NAME
update \- A copy program that recursively updates directory trees
.SH SYNOPSIS
\fBupdate\fR [\fIoptions\fR] \fIsrc1 ... srcN targetDir\fR
.br
\fBupdate\fR [\fIoptions\fR] \fIsrc target\fR
.SH OPTIONS
.IP "\fB\-b \fIdirectory\fR" 15
Before updating a target, save a backup copy of the file in
\fIdirectory\fR.
.IP "\fB\-B \fIdays\fR" 15
Only save the target as a backup copy if no backup exists or if the
target is \fIdays\fR days old.
.IP "\fB\-f\fR" 15
Force:  always update targets regardless of last-modified times.
.IP "\fB\-g \fIgroup\fR" 15
Change the group of any updated files to \fIgroup\fR.  Targets that aren't
updated do not have their groups changed.
.IP "\fB\-help\fR" 15
Print a summary of the command-line options and exit without updating
any targets.
.IP "\fB\-l\fR" 15
If a source file is a symbolic link then \fBupdate\fR normally creates an
identical symbolic link at the destination.  If the \fB\-l\fR switch
is specified, then \fBupdate\fR copies the file referenced by the source link,
rather than the link itself.
.IP "\fB\-L\fR" 15
Creates symbolic links to non-directory source files, rather than copying them.
Directories
are copied in the normal manner. This flag is useful for creating shadow
trees of source directories. If either the source or the destination
start with '/' the link will be absolute, otherwise it's relative.
.IP "\fB\-m \fImode\fR" 15
When updating a target, set its protection bits to \fImode\fR.  Targets
that aren't updated do not have their protection changed.  \fIMode\fR
must be specified in octal.
.IP "\fB\-n\fR" 15
Be nice about problems with file types not matching (i.e. don't return
an error).
.IP "\fB\-M\fR" 15
When updating a target, do it by moving the source instead of by
copying.  This may be useful when disk space is tight.
.IP "\fB\-o \fIowner\fR" 15
Perform all updates as user \fIowner\fR, so that newly-created targets
will be owned by \fIowner\fR.  Any targets that are not updated will
not have their \fIowner\fR changed.
.IP "\fB\-O\fR" 15
This option preserves ownership on newly created files.  Only root or
wheel group members can use this option.
.VS
.IP "\fB\-p \fIpruneExpr\fR" 15
Prune subtress whose name matches the given regular expression.
.VE
.IP "\fB\-q\fR" 15
Quiet.  Don't print anything except for error messages.  \fBUpdate\fR normally
prints a message for each file copied.
.IP "\fB\-s\fR" 15
Strip.  Source files are all expected to be executable binaries.  When
copying, strip all of the symbol and relocation information from the
updated target.
.IP "\fB\-t\fR" 15
Instead of setting the last-accessed and last-modified times of each
target to match those of its source, leave them alone, so that they are
set to the current time.
.IP "\fB\-v\fR" 15
Verify.  Don't actually modify any files, but print information about
which files would have been modified.
.BE

.SH INTRODUCTION
.PP
The \fBupdate\fR command is used to replace out-of-date copies of files with
more recent versions.  It operates on one or more source files.  For
each source, \fBupdate\fR locates a corresponding target;  if the target
doesn't exist, or if the last-modified
time of the source is later than the last-modified time
of the target, or if the \fB\-f\fR option
is specified, then \fBupdate\fR makes a copy of the source at the target.
The target's last-modified time and permissions will be set identical
to those of the source.
.PP
In the simplest case, two file names are given, both of which are
regular files.  In this case the first file name is the source and
the second is the target.  If the last file name refers to
a directory, then all the other file names (of which there may be
more than one) are sources.
Each source file will be updated to the corresponding file
\fIwithin\fR the target directory.  For example, in the command
.DS
\fBupdate /a/b c d foo\fR
.DE
the target for \fB/a/b\fR will be \fBfoo/b\fR, the target for \fBc\fR
will be \fB/foo/c\fR, and the target for \fBd\fR will be \fBfoo/d\fR.
.PP
If any of the source files is a directory, then its entire subtree will
be updated to the corresponding target, maintaining the subtree
structure of the
source.  In the special case where only two file names are given
and both are directories, then the source is updated \fIto\fR
the target directory rather than \fIwithin\fR it.  Thus, in the command
.DS
\fBupdate a b\fR
.DE
where \fBa\fR and \fBb\fR are both directories and
\fBa\fR contains one subdirectory \fBc\fR which in turn
contains one file \fBd\fR, the target corresponding
to \fBa/c/d\fR will be \fBb/c/d\fR.  \fBUpdate\fR will create the
directory \fBb/c\fR if it doesn't already exist.
.PP
\fBUpdate\fR will also copy symbolic links.  Normally it creates matching
symbolic links at the targets, but it will copy the files pointed to
by the links if the \fB\-l\fR switch is given.
.PP
If the target for a source already exists but has a type different from
the source (e.g. the target is a directory and the source is a regular
file), then \fBupdate\fR will not modify the target.  If the target's last-modified
time is more recent than the source's, then again \fBupdate\fR will not modify
the target.

.SH "USER AND GROUP CHANGES"
.PP
There are several restrictions on usage of the \fB\-O\fR, \fB\-o\fR and \fB\-g\fR
switches.
You may specify \fB\-O\fR only if you are root or in the wheel group.
You may specify \fB\-g \fIgroup\fR as long as you are a member
of \fIgroup\fR.
You may specify \fB\-o \fIowner\fR if either
.IP [1]
You are \fIowner\fR (which isn't very interesting).
.IP [2]
\fIOwner\fR is \fBroot\fR, and you are a member of the \fBwheel\fR group.
.IP [3]
There is a group with the same name as \fIowner\fR and you are a member
of that group.

.SH "SET-USER_ID"
.PP
If you haven't specified the \fB\-m\fR switch, then \fBupdate\fR attempts
to preserve set-user-id bits.  It also attempts to preserve set-user-id
bits when making backup copies, even if the \fB\-m\fR switch was given.
However, set-user-id bits are not preserved unless the owner of the
target file is the same as the owner of the source file (this condition
is always true if the \fB\-O\fR switch is given).

.SH "BACKUP FILES"
.PP
If the \fB\-b\fR switch is specified, then \fBupdate\fR attempts to
ensure that a backup copy of the target is saved, if the target
already exists.  If a backup already exists, then the backup is
overwritten only if the target is relatively old (a parameter that
defaults to files two weeks old and may be overridden by the \fB-B\fR
switch, specifying the requisite age in days).  If the \fB-B\fR switch
specifies an age of 0, then the most
recent target will always be backed up.  Normally, the default of 14
(two weeks) is used to guarantee that an unstable file does not
overwrite a stable backup.

.VS
.SH "PRUNING SUB-TREES"
.PP
The \fB\-p\fR option can be used to prune unwanted sub-trees from the source
files. The argument is a regular expression that is matched against all source
files before updating them.  If the expression matches then the source is
not updated.  The expression is matched against only the tail of the source
path name, so using an expression of "foo/bar" will not do what you think
it will. If the argument contains any magic characters such as "*" then you
better put it inside of quotes otherwise csh will glob it first.  Multiple
\fB\-p\fR options can be specified and will be compared against the source files
one at a time.
.VE
.SH KEYWORDS
copy, up-to-date

.SH "SEE ALSO"
cp, mv, tar