Martin Marques wrote:
CVS has problems caused by all of the history being kept in a single
file (it doesn't understand directory operations like renames), but the
Oh, and the fact that commits are not atomic so that if two chagesets
collide (well, CVS doesn't have notion of changeset, only of single file
changes) very bad things can happen (one changeset locks a file that the
other changeset has to update) and you get a corrupt copy that has to be
fixed.
Subversion, git and Mercurial (and others) addressed this issue adding
atomicity to the chagesets (see that with these VCS files don't have
version there are changeset versions).
up side is that you can track development 'forwards' from any point.
Uhh???
$ hg up -r SOME_OLD_REV
Start from a tagged point in development. Branch several times for
different changes. Can you find all subsequent work?
(same with svn or git-update).
With svn, there's no way to start from an earlier tag and follow
future tags/branches of that same file.
What? Les do you really know what you're talking about?
I'd like to hear that I don't. With CVS, if you have any of the
development you have all of it. With svn, tags are (by convention) dead
end snapshots and there is no way to track forward development. Assume
you worked on something some time ago, ending by creating a certain tag.
Now several other people create branches for additional work. How can
you tell that, starting from the tag you last knew about? You could
start from any of the branches and work backwards but you can't see what
branches were created or when going forwards.
This must be even worse in distributed VC's where the changes might
not even exist in your copy of the repository. Doesn't it bother you
to know you might be repeating someone else's mistakes because you
can't track all the other changes from a given point?
What mistake if it's not in the repository?
That's the point - you won't know.
The same thing would happen with CVS if you were coding without
commiting to the main server. Nobody will be able to know what you are
doing. Same if your coworkers don't update regularly. How can they know
what you fixed?
If you aren't committing to the central repository, you aren't using CVS.
In distributed VCS you use pull and push for this.
How can you tell whether that was always done or not?
--
Les Mikesell
lesmikesell@xxxxxxxxx
