CVS Lock Files - what, where, when, how, etc.

[bdcutler2001]

Hello.  I have noticed several different kind of lockfiles that CVS
seems to create (and sometimes leave laying around) and was hoping 
someone could help me out on what they are used for, when are they 
created, where they are created, and when are they removed.

Here are the ones that I know about:

LOCKDIRS
   #CVS.LOCK - created when a file is being checked out.  
               Any other time?  
               Create din the lockdirs directory.
               Once per operation?

   RFL/WFL lock - created on every read (the rfl file) and write
                  the wfl file?  
                  Seems to be in the lockdirs only directory.  If
                  I am not mistaken, these are files actually tied
                  to the read or write processes.  Why do they get
                  left around?

   ,file, - every time file is updated in the repository, this
            file is created in the directory the ,v file resides
            in.  Destroyed (actually copied over ,v) at end of 
            write operation.

Any help you folks can provide is greatly appreciated.

Brian Cutler