CVS - Common options

There are common options for cvs commands:

-a
Authenticate all communication between the client and the server. Only has an effect on the CVS client. As of this writing, this is only implemented when using a GSSAPI connection. Authentication prevents certain sorts of attacks involving hijacking the active TCP connection. Enabling authentication does not enable encryption.
-T tempdir
Use tempdir as the directory where temporary files are located. Overrides the setting of the $TMPDIR environment variable and any precompiled directory.
This parameter should be specified as an absolute pathname.
-d cvs_root_directory
Use cvs_root_directory as the root directory pathname of the repository. Overrides the setting of the $CVSROOT environment variable.
-e editor
Use editor to enter revision log information. Overrides the setting of the $CVSEDITOR and $EDITOR environment variables.
-f
Do not read the `~/.cvsrc' file. This option is most often used because of the non-orthogonality of the CVS option set. For example, the `cvs log' option `-N' (turn off display of tag names) does not have a corresponding option to turn the display on. So if you have `-N' in the `~/.cvsrc' entry for `log', you may need to use `-f' to show the tag names.
 
-H
--help
Display usage information about the specified `cvs_command' (but do not actually execute the command). If you don't specify a command name, `cvs -H' displays overall help for CVS, including a list of other help options.
-n
Do not change any files. Attempt to execute the `cvs_command', but only to issue reports; do not remove, update, or merge any existing files, or create any new files. Note that CVS will not necessarily produce exactly the same output as without `-n'. In some cases the output will be the same, but in other cases CVS will skip some of the processing that would have been required to produce the exact same output.
-x
Encrypt all communication between the client and the server. Only has an effect on the CVS client. As of this writing, this is only implemented when using a GSSAPI or a Kerberos connection.
Enabling encryption implies that message traffic is also authenticated. Encryption support is not available by default; it must be enabled using a special configure option, `--enable-encryption', when you build CVS.
-z gzip-level
Set the compression level. Only has an effect on the CVS client.