You do not remember modifying `driver.c', so you want to see what has happened to that file.
$ cd tc $ cvs diff driver.c
This command runs
diff to compare the version of `driver.c'
that you checked out with your working copy. When you see the output
you remember that you added a command line option that enabled the
optimization pass. You check it in, and release the module.
$ cvs commit -m "Added an optimization pass" driver.c Checking in driver.c; /usr/local/cvsroot/tc/driver.c,v <-- driver.c new revision: 1.2; previous revision: 1.1 done $ cd .. $ cvs release -d tc ? tc You have  altered files in this repository. Are you sure you want to release (and delete) directory `tc': y