Environment Variables

Environment Variables

Several environment variables affect CVS. Some are read-only when CVS is the client, and some are read-only when CVS is the server. When the repository resides on the local machine, both sets are read.

Client Environment Variables

The environment variables in the following list are read and used by the process that runs on the client computer and must be in the calling user's environment:

CVS_CLIENT_LOG

Used for debugging CVS in client/server mode. If set, everything sent to the server is stored in the $CVS_CLIENT_LOG.in file, and everything received by the client is stored in $CVS_CLIENT_LOG.out.

CVS_CLIENT_PORT

Used to set the port the client uses to connect to the CVS server in kserver, gserver, and pserver modes. By default, the client uses port 2401 (gserver and pserver) or port 1999 (kserver) to connect to the server.

CVSIGNORE

A whitespace-separated list of filename patterns that should be ignored. See the description of the .cvsignore file, earlier in this chapter.

CVSEDITOR, EDITOR, VISUAL

Used to set the editor CVS calls when it opens an editor for log messages. On Unix and GNU/Linux systems, the default editor is vi. Using CVSEDITOR is preferred over EDITOR and VISUAL, as other variables may be used by other programs.

CVS_PASSFILE

Used to change the file CVS uses to store and retrieve the password in pserver remote-access mode. The default file is $HOME/.cvspass.

CVSREAD

If set to 1, CVS tries to check out your sandbox in read-only mode. (CVS actually checks whether this variable is nonnull, so it works regardless of the setting. This behavior may change in the future.)

CVSROOT

Contains the full pathname of the CVS repository. When you're working in a sandbox, this variable is not needed. If you're working outside a sandbox, either this variable must be present or the -d repository_path option must be used.

CVS_RSH

Used to set the program CVS calls to connect to a remote repository in ext mode. The default program is rsh.

The rsh command is unacceptably insecure. You should avoid it completely; use ssh instead.

CVS_SERVER

If connecting to a CVS server using rsh, this variable is used to determine which program is started on the server side. In ext and server modes, this defaults to cvs. When the repository is on the local system, this defaults to the path to the CVS client program.

CVSWRAPPERS

May contain no more than one wrapper, as explained in CVS Wrappers," earlier in this chapter.

HOME, HOMEPATH, HOMEDRIVE

Used to determine where the user's home directory is, to enable CVS to locate its files. On Unix, GNU/Linux, and related systems, only HOME is used. On Windows systems, HOMEDRIVE and HOMEPATH are used. Some Windows operating systems (Windows NT, 2000, and XP) set these variables automatically. If yours doesn't, HOMEDRIVE should be set to the drive letter (e.g., C:), and HOMEPATH should be set to the path (e.g., \home\arnold).

PATH

Used to locate any programs whose path is not compiled with the CVS program. This variable is still used, but it is less important now that the rcs, diff, and patch programs CVS uses are all distributed with CVS.

Server Environment Variables

The following variables are read when CVS is operating as the server (or when the repository is on the local system). They must be in the calling user's environment on the server computer.

CVS_SERVER_SLEEP

Used only when debugging the server in client/server mode. This variable delays the start of the server client process by CVS_SERVER_SLEEP seconds to allow the debugger to be attached to it.

CVSUMASK

Used to set the default permissions of files in the repository. This variable may be added to the client code in a later version of CVS.

PATH

Used to locate any programs whose path is not compiled with the CVS program. This variable is still used, but it is less important now that the rcs, diff, and patch programs CVS uses are all distributed with CVS.

TMPDIR

Sets the temporary directory CVS stores data in. This variable defaults to /tmp.

CVS creates temporary files with mkstemp (BSD 4.3), if possible. If mkstemp is not available when CVS is compiled, it tries tempnam (SVID 3), mktemp (BSD 4.3), or tmpnam (POSIX), in that order. If it uses tmpnam, it cannot use the TMPDIR environment variable, and files are created in /tmp.