AVR Freaks

Note on a VCS
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Simon Large wrote in with some interesting comments about an open source
version control system:

In my previous company I used Visual SourceSafe (VSS) all the time. When I
changed jobs, the new company (managed by mechanical engineers) could not
accept that a VCS was better than using WinZip periodically, and would not
pay. As a result, I trawled around the open source sites and came across
Subversion. This project was started in around 2000 as a replacement for
the ageing CVS system widely used by the open source community, but rather
limited in scope. You can read the history for yourself on their site, but
it is now widely deployed and seems well regarded.

Many of the enhancements over CVS also apply with regard to VSS, but in
particular:
* Atomic commits - A change often involves several files. In this system
you check them all in together in one operation with a single log message.
If any file fails, the whole commit fails, so you don't end up with the
repository in a half-changed state.

* Ported to many OSes - The server component is based on the Apache web
server and will run on a wide variety of machines. Likewise the client.

* Flexibility - You can also use the client standalone on a local PC; or
several clients on a network share; or you can set up a server and access
over LAN or the Internet using Apache's security.

* Works with large databases - VSS is notorious for database corruption
when the number of files rises. Subversion is being used to store multi
Gigabyte projects (not embedded!!!)

* Free! - VSS costs around $300 per user, and if you want to use it over
the internet you need something like SourceOffsite, also around $300.
Perforce is also highly regarded, but costs around $750 per user (although
to be fair you can use Perforce for free, but restricted to 2 users and 2
working directories).

* Support - There is an active mailing list and you get good technical info
quickly (unlike many mailing lists where you just get "this product is
cool/this product sucks" with zero information content).

Although it is open source, most users never see the source - you just
download the precompiled binaries and install.

The standard client is a command line interface, but of particular interest
to Windows users is the TortoiseSVN client. This integrates into Windows
explorer as a shell extension and you get VCS instantly in your right mouse
context menu. It is very easy to use and the documentation is excellent (I
have to say that because, like Victor Kiam, I was so impressed I joined the
TSVN project). If you don't need the server component, TSVN is all you need
to download.

Also of interest to you, project rules which govern how changes are made to
the project code and documentation are a model of good software practice.
ALL changes are reviewed by the development team, and they are really picky
about quality of comments as well as the code itself.

This has come across as more of a sales pitch than I originally intended,
but when I see a good product which can be of real help to other engineers
I like to tell them about it.

The main subversion website is at http://subversion.tigris.org

The TortoiseSVN (Windows client) is at http://tortoisesvn.tigris.org