GNU Screen rocks, in general, but recently I've been using it a lot for custom applications and have discovered a pair of annoying bugs.

If you're not familiar with it then please read this GNU Screen tutorial - it really is worth getting to know!

Anyway onto the bugs:

• Session names may not start with numbers.
• Session names must be globally unique.

The two are related, but I'm not yet sure whether I should report bugs against the Debian package and the code is sufficiently cryptic that I cannot create a fix yet.

Taking the bugs in reverse order please try this:

screen -S foo
[detach]
screen -S foo2
[detach]

At this point you should have two screen sessions "foo" and "foo2". You should be able to attach to them by running "screen -R foo" or "screen -R foo2". Lets try that:

skx@vain:~$ screen -R foo
There are several suitable screens on:
        22317.foo       (Detached)
        22342.foo2      (Detached)
Type "screen [-d] -r [pid.]tty.host" to resume one of them.

Even though foo should be sufficient to identify a unique screen, the first one, it doesn't let you attach. Nasty.

(Yes, you can attach to it if you use the number/number+name:

screen -R  22317.foo 

The second issue is related. Create a screen session with "screen -S 222". Now try to attach to it with "screen -R 222" - instead of attaching it gives you a brand new screen.

Ugh.

Tags: bugs, gnu screen, screen | No comments