cvslock − lock CVS repositories


cvslock [-q] [-p pid] [-d CVS root] [-R|-W] [-u|-s|-c Command] [-l] directory


cvslock is used to lock a tree starting at directory in your CVS repository during low-level manipulation or inspection.

There are various modes of operation: You can use the -s or -c options to cause cvslock to spawn a sub-shell or a shell command from which you can safely access the source repository.

You can also use cvslock to lock and unlock CVS repositories from shell scripts; in this case you’ll want to use the -p option to specify the process ID which is written to the lock files’ names.

The default when given no options is to acquire a persistant read lock.



This option tells cvslock to shut up and not print any diagnostic messages to stdout. This is most useful when using the program in conjunction with, e.g., rsync(1).

-p pid

The CVS lock files generated by this utility have the current process ID in their name to distinguish them from lock files generated by other tools such as cvs itself or concurrent sessions of cvslock. Use this option to force cvslock to use a specific pid. This is in most useful from shell scripts.

-d CVS root

This optional argument tells cvslock where your CVS repository’s root is. If no -d switch is given, cvslock will fall back to the CVSROOT environment variable. Note that cvslock only works on local repositories, so don’t try to access pserver or rsh-accessible remote repositories this way.


This switch tells cvslock to acquire a lock for safe reading of the repository.


This switch tells cvslock to acquire a write lock on the repository.


When invoked with this option, cvslock will invoke the user’s login shell as determined by the SHELL environment variable after locking the repository. After the user has left that shell, cvslock will drop the locks.

-c Command

This option is similar to the -s option, with the difference that cvslock will execute the shell command given on the command line instead of giving the user an interactive shell.


When given this option, cvslock will try to drop a previously created lock on the repository in question. Using this option together with the -s or -c options is an error. The use of -p is highly recommended in conjunction with this option!


This option tells cvslock to lock only the directory specified. Normally it locks the entire directory hierarchy under the specified directory.


cvslock spits out some diagnostics to the standard error stream. It’s exit value is zero if and only if the locking operation requested by the user could be performed successfully. Note that no diagnostics about the exit value of commands executed through the -c switch are given.


The signal handling is not too well-tested and may be broken.

If you try to create the same lock several times, you will get funny effects due to the error recovery cvslock tries to do.


Version Management with CVS

rsync(1), system(3), cvs(1)


cvslock was put together in a quick hacking session by Thomas Roessler <> and may be distributed under the terms of the GNU General Public License version 2.


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