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Re: Cygwin 1.7 GNU screen freezing when disconnected
On Thu, Dec 17, 2009 at 1:06 PM, Andrew Schulman wrote:
> Karim, I'm afraid that I don't have much to offer here. ÂA few thoughts:
> After you kill ssh, what does screen -list say?
After I kill ssh, screen -list doesn't do anything. It basically
becomes unresponsive as well.
> You probably know that when you're connected to a screen session, there are
> two screen processes, which communicate with each other through a socket.
> When you detach, the foreground screen process exits but the background one
> stays around, waiting for a new attach. ÂIt seems that when you kill ssh,
> somehow data stops flowing to or from the background screen process from
> that socket. ÂAnd that unfortunately is about as deep as my knowledge of
> screen goes.
> strace can probably point to the problem, although I don't know if I have
> the ability to find it. ÂOthers on this list probably can. ÂI would think
> of looking at strace output for the following:
> * the background screen process (i.e., the one that stays running when you
> detach from it) at the time you kill ssh, especially compared to when you
> detach from it normally.
> * the foreground and background screen processes when you try to reattach
> after having killed ssh. ÂAgain this might be most useful when compared to
> a successful reattach after a normal detach.
> If you post or link to this, I'll take a look and maybe I or someone else
> can find the problem.
I'm sorry, I'm not really sure how to use strace. What I am currently
doing is (for the background process):
- Run screen, detach from the screen session
- Find the PID of the remaining screen process
- Attach to it with strace using: strace -o screen_bg -p <PID>
- Attach to the screen session, detach, reattach and then run 'exit'
in the session
After I do this strace has ended and the screen_bg file has no output
in it. Is there something I'm doing wrong or is this normal?
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