On 7/26/07, Thomas Klausner <wiz@netbsd.org> wrote:
> Hi!
>
> Lately, screen started misbehaving -- it sometimes doesn't reattach
> detached sessions. I'm using 4.99.25/amd64.
>
> I'm not quite sure what I have to do to reproduce this, but I
> currently have that state on one of my machines.
>
> # ll /tmp/screens/S-wiz/
> total 4
> drwx------  2 wiz   users  512 Jul 25 10:01 .
> drwxr-xr-x  3 root  wheel  512 Jul 23 13:53 ..
> prwx------  1 wiz   users    0 Jul 26 00:34 28211.ttyp0.hiro
> srw-------  1 wiz   users    0 Jul 25 08:20 467.ttyp0.hiro
>
> The 28211 one is a session I can still use, but I can't attach to the
> 467 one.
>
> From ps output:
> root       467  0.0  0.0  1372  2324 ?     IWs  Mon01PM 0:00.00 SCREEN -d -RR -e^zz (screen-4.0.3)
> root     28211  0.0  0.3  1680  2812 ?     Ss   10:01AM 0:00.00 SCREEN -d -RR (screen-4.0.3)
> wiz      29758  0.0  0.2   528  1764 ttyp5 Ss+  12:34AM 0:00.00 screen -d -RR -e^Zz (screen-4.0.3)
>
> # screen -r 467.ttyp0.hiro
> There is no screen to be resumed matching 467.ttyp0.hiro.
>
> Any ideas what's happening here?


On my box screens seem to be of type p (named pipe, I think) and have
the permissions 600. (although your working screen seems to have a
700)

Your non-working screen session has somehow managed to transform into
a unix socket.  I wonder if you can ktrace detaching until you do it
again.