Sometimes a working copy's revision has extra data
associated with it, for example it might be on a branch
(see Branching and merging), or restricted to
versions prior to a certain date by `
update -D'. Because this data persists --
that is, it applies to subsequent commands in the
working copy -- we refer to it as sticky.
Most of the time, stickiness is an obscure aspect of CVS that you don't need to think about. However, even if you don't want to use the feature, you may need to know something about sticky tags (for example, how to avoid them!).
You can use the
status command to see if any
sticky tags or dates are set:
$ cvs status driver.c =================================================================== File: driver.c Status: Up-to-date Version: 18.104.22.168 Sat Dec 5 19:35:03 1992 RCS Version: 22.214.171.124 /u/cvsroot/yoyodyne/tc/driver.c,v Sticky Tag: rel-1-0-patches (branch: 1.7.2) Sticky Date: (none) Sticky Options: (none)
The sticky tags will remain on your working files until
you delete them with `
cvs update -A'. The
-A' option retrieves the version of the file from
the head of the trunk, and forgets any sticky tags,
dates, or options.
The most common use of sticky tags is to identify which
branch one is working on, as described in
Accessing branches. However, non-branch
sticky tags have uses as well. For example,
suppose that you want to avoid updating your working
directory, to isolate yourself from possibly
destabilizing changes other people are making. You
can, of course, just refrain from running
cvs update. But if you want to avoid updating only a
portion of a larger tree, then sticky tags can help.
If you check out a certain revision (such as 1.4) it
will become sticky. Subsequent
not retrieve the latest revision until you reset the
cvs update -A. Likewise, use of the
-D' option to
sets a sticky date, which, similarly, causes that
date to be used for future retrievals.
Many times you will want to retrieve an old version of
a file without setting a sticky tag. The way to do
that is with the `
-p' option to
update, which sends the contents of the file to
standard output. For example, suppose you have a file
file1' which existed as revision 1.1, and
you then removed it (thus adding a dead revision 1.2).
Now suppose you want to add it again, with the same
contents it had previously. Here is how to do it:
$ cvs update -p -r 1.1 file1 >file1 =================================================================== Checking out file1 RCS: /tmp/cvs-sanity/cvsroot/first-dir/Attic/file1,v VERS: 1.1 *************** $ cvs add file1 cvs add: re-adding file file1 (in place of dead revision 1.2) cvs add: use 'cvs commit' to add this file permanently $ cvs commit -m test Checking in file1; /tmp/cvs-sanity/cvsroot/first-dir/file1,v <-- file1 new revision: 1.3; previous revision: 1.2 done $