Here is a sample login command from the fine book, Open Source Development with CVS:

  cvs -d :pserver:jrandom@cvs.foobar.com:/usr/local/cvs login

This example assumes the following:

• You have a CVS client installed on your system.
• You are using the pserver access method.
• You are accessing a repository on a server named cvs.foobar.com.
• The CVS directory on that server is /usr/local/cvs.
• Your username on that server is jrandom.

If everything works ok, you will be prompted to enter your password.

Note that another thing you can do here is set your CVSROOT before logging in. For example, using ksh you can set your CVSROOT environment variable like this:

export CVSROOT=:pserver:al@cvs.devdaily.com:/cvs

Then you can just login like this:

cvs login

This tends to be a little easier, at least for me. Actually, I've set up a bunch of aliases for the half-dozen or so CVS servers I usually connect to.