attach to byobu crashes on hardy

Hello,

Can you please run the following, and attach /tmp/out

 $ sh -x /usr/bin/screen true 2>/tmp/out

:-Dustin

Also, please run this, and attach /tmp/out:
 $ sh -x /usr/bin/screen 2>/tmp/out

:-Dustin

sh -x /usr/bin/screen true 2>/tmp/out

+ OLDPKG=screen-profiles
+ PKG=byobu
+ [ -d /root/. -a ! -e /root/.byobu ]
+ [ -d /root/.byobu ]
+ [ -n -a -r ]
+ SCREENRC=/root/.screenrc
+ [ -r /root/.screenrc -a ! -e /root/.byobu/profile -a ! -h /root/.byobu/profile ]
+ DEFAULT_PROFILE=light
+ profile=/root/.byobu/profile
+ [ -h /root/.byobu/profile ]
+ [ -h /root/.byobu/profile -a ! -r /root/.byobu/profile ]
+ [ ! -r /root/.byobu/profile ]
+ [ -s /root/.byobu/keybindings ]
+ sed -i s/screen-profiles/byobu/g /root/.byobu/keybindings
+ [ -r /root/.byobu/windows ]
+ [ -r /root/.screenrc ]
+ [ 1 = 0 ]
+ exec /usr/bin/screen.real -c /root/.byobu/profile true

sh -x /usr/bin/screen 2>/tmp/out

+ OLDPKG=screen-profiles
+ PKG=byobu
+ [ -d /root/. -a ! -e /root/.byobu ]
+ [ -d /root/.byobu ]
+ [ -n -a -r ]
+ SCREENRC=/root/.screenrc
+ [ -r /root/.screenrc -a ! -e /root/.byobu/profile -a ! -h /root/.byobu/profile ]
+ DEFAULT_PROFILE=light
+ profile=/root/.byobu/profile
+ [ -h /root/.byobu/profile ]
+ [ -h /root/.byobu/profile -a ! -r /root/.byobu/profile ]
+ [ ! -r /root/.byobu/profile ]
+ [ -s /root/.byobu/keybindings ]
+ sed -i s/screen-profiles/byobu/g /root/.byobu/keybindings
+ [ -r /root/.byobu/windows ]
+ [ -r /root/.screenrc ]
+ [ 0 = 0 ]
+ mktemp -t byobu-XXXXXXXX
+ temp=/tmp/byobu-CwC19723
+ cat /root/.byobu/profile /root/.byobu/windows
+ [ -n /bin/bash -a -x /bin/bash ]
+ exec /usr/bin/screen.real -c /tmp/byobu-CwC19723 /bin/bash /usr/bin/motd+shell /tmp/byobu-CwC19723

Okay, how about

 $ ls -alF / | grep tmp

I'm checking the permissions on your /tmp directory.

:-Dustin

Also, could you try one thing ...

Make a backup copy of /usr/bin/motd+shell, and edit the original.

Comment out the line that says:

[ -n "$1" -a -w "$1" ] && rm -f "$1" 2>/dev/null

This will disable the cleanup of the tempfile. Once you've done this,
try running this again:

 $ sh /usr/bin/screen 2>/tmp/out

Check the output of /tmp/out for the name of the tempfile. See if that exists.

:-Dustin

Well root has access to /tmp. The /tmp/byobu-XXXXXXX is removed when screen.real executes.

drwxrwxrwt 4 root root 112 2009-05-12 16:25 tmp

removing [ -n "$1" -a -w "$1" ] && rm -f "$1" 2>/dev/null makes it work, but has the side effect that
/tmp/byobu-tpM10227 isn't removed when screen exits.

+ OLDPKG=screen-profiles
+ PKG=byobu
+ [ -d /root/. -a ! -e /root/.byobu ]
+ [ -d /root/.byobu ]
+ [ -n -a -r ]
+ SCREENRC=/root/.screenrc
+ [ -r /root/.screenrc -a ! -e /root/.byobu/profile -a ! -h /root/.byobu/profile ]
+ DEFAULT_PROFILE=light
+ profile=/root/.byobu/profile
+ [ -h /root/.byobu/profile ]
+ [ -h /root/.byobu/profile -a ! -r /root/.byobu/profile ]
+ [ ! -r /root/.byobu/profile ]
+ [ -s /root/.byobu/keybindings ]
+ sed -i s/screen-profiles/byobu/g /root/.byobu/keybindings
+ [ -r /root/.byobu/windows ]
+ [ -r /root/.screenrc ]
+ [ 0 = 0 ]
+ mktemp -t byobu-XXXXXXXX
+ temp=/tmp/byobu-tpM10227
+ cat /root/.byobu/profile /root/.byobu/windows
+ [ -n /bin/bash -a -x /bin/bash ]
+ exec /usr/bin/screen.real -c /tmp/byobu-tpM10227 /bin/bash /usr/bin/motd+shell /tmp/byobu-tpM10227

Hmm, strange.

I suppose motd+shell must be removing the temp file too quickly,
before screen.real has had a chance to read it.

I'll have to think on this one a bit.

Since I can't reproduce this, I'll probably need you to test a fix,
once I have it :-)

:-Dustin

It's not a especially fast server I'm running it on. 2x2.4 xeon with sata drives, and 2 gigs of memory.

I will be able to try a fix when you have thought about it :)

But from my understanding the motd-shell is executing when screen starts, and then removes the /tmp/byobu file?

When detaching one screen session with ctrl-a d, or f6, and returning again with screen -r this file is needed by screen? So maybee it should only be removed when screen is stopped.

Sorry if I missread the code totally.

I produce the problem on hardy by doing (working ok on jaunty)
screen
f6
screen -r

What version of byobu are you running on each of these two systems,
hardy and jaunty?

:-Dustin

Ah, okay, now I have reproduced this. It was not clear to me until
your last message that this happens when doing a detach, then
re-attach.

Looks like this is a difference in the way the screen binary on hardy
behaves, from the one in jaunty. I'll need to do some digging.

:-Dustin

running:

byobu 2.3-0ubuntu1~ppa1
byobu-extras 2.3-0ubuntu1~ppa1
screen 4.0.3-7ubuntu1.1~ppa2

(screen was upgraded to the package in the byobu PPA)

on

Description: Ubuntu 8.04.2
Release: 8.04
Codename: hardy

2.6.24-24-generic #1 SMP Wed Apr 15 15:54:25 UTC 2009 i686 GNU/Linux

and i too am unable to reattach to a screen session after detaching.

$ screen -r
Unable to open "/tmp/byobu-xHC31224".

have tried reverting to
screen 4.0.3-7ubuntu1
(as packaged by default in hardy)
but the problem remains:

$ screen -r
Unable to open "/tmp/byobu-TPD31569".

however, both version function correctly when byobu is not installed.

I have a good, clean fix for this, will be in 2.4 release.

:-Dustin