Chapter 6

your module distribution directory. You shouldn't include derivative files such as 

Makefile or the contents of blib in CVS, so make sure you run a make clean first to 

remove them.

Next, you'll need to choose a CVS module name and import your source. CVS 

module names are unique identifiers that you'll use to access you files in CVS. By 

including module names, a single CVS repository can house any number of inde 

pendent source trees. An easy way to create a name that CVS will accept is to use 

your module's distribution filename minus the version information. For example, 

to import the source for Data::Counter into CVS, I would use this command in the 

Data::Counter distribution directory:

$ cvs import  m "Import of Data::Counter" Data Counter vendor start

The  m option specifies a log message for the import if you leave it out, then CVS 

will open an editor for you to enter a log message. Most CVS commands accept a 

log message that can later be viewed with the cvs log command. After that comes 

the module name Data Counter. The last two arguments are the  vendor  tag 

and the  start  tag. Unless you're a total CVS nerd, you'll never use either of these, 

so you can set them to whatever you want. They're theoretically useful in tracking 

third party sources through CVS. Or something like that.

Getting a Working Copy

To use CVS to manage the files you just imported, you need to check out a working 

copy of your source. To do so, use the cvs checkout command:

$ cvs checkout Data Counter

U Data Counter/Changes

U Data Counter/Counter.pm

U Data Counter/MANIFEST

U Data Counter/Makefile

...

The output from the checkout command will show you the files and directories 

being created from the CVS repository; the leading U stands for updated. Your 

working copy contains all the same stuff that your module distribution does 

except that each directory also has a CVS directory that contains special CVS files. 

I won't go into the contents of these files, but you should be careful not to delete 

them or you'll have to check out a new working copy.

A CVS checkout does not lock the files being checked out, as is the case in 

some version control systems. CVS allows many developers to work on the same 

files simultaneously and will automatically merge changes. If changes cannot be 

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