Re: Bug#644788: Bug#654116: RFH: screen -- terminal multiplexor with VT100/ANSI terminal emulation

2012-01-10 Thread Thomas Goirand
On 01/04/2012 10:24 PM, Axel Beckert wrote: Hi Simon, Simon McVittie wrote: On Mon, 02 Jan 2012 at 16:26:55 -0500, Yaroslav Halchenko wrote: On Mon, 02 Jan 2012, Axel Beckert wrote: /tmp is a good choice because the next reboot will automatically clean up everything (and

Re: Bug#644788: Bug#654116: RFH: screen -- terminal multiplexor with VT100/ANSI terminal emulation

2012-01-04 Thread Axel Beckert
Hi Tollef, Tollef Fog Heen wrote: Not really a serious suggestion, but for completeness E) ignore the problem and just let people rescue the programs stuck in the old screen using retty, reptyr or similar. My experiences with one of these tools (IIRC retty, but I'm not sure) a few years ago

Re: Bug#644788: Bug#654116: RFH: screen -- terminal multiplexor with VT100/ANSI terminal emulation

2012-01-04 Thread Roger Leigh
On Tue, Jan 03, 2012 at 04:04:04PM +0100, Axel Beckert wrote: Hi, Roger Leigh wrote: [/tmp mounted noexec] /run/shm (IIRC formerly /dev/shm) likely would be an alternative option, too. No, it would not. This directory is reserved for the eglibc POSIX SHM/SEM interfaces.

Re: Bug#644788: Bug#654116: RFH: screen -- terminal multiplexor with VT100/ANSI terminal emulation

2012-01-04 Thread Simon McVittie
On Mon, 02 Jan 2012 at 16:26:55 -0500, Yaroslav Halchenko wrote: On Mon, 02 Jan 2012, Axel Beckert wrote: /tmp is a good choice because the next reboot will automatically clean up everything (and obviously the old binary will not be needed after a reboot). Thank you Axel for your

Re: Bug#644788: Bug#654116: RFH: screen -- terminal multiplexor with VT100/ANSI terminal emulation

2012-01-04 Thread Axel Beckert
Hi Simon, Simon McVittie wrote: On Mon, 02 Jan 2012 at 16:26:55 -0500, Yaroslav Halchenko wrote: On Mon, 02 Jan 2012, Axel Beckert wrote: /tmp is a good choice because the next reboot will automatically clean up everything (and obviously the old binary will not be needed after a

Re: Bug#644788: Bug#654116: RFH: screen -- terminal multiplexor with VT100/ANSI terminal emulation

2012-01-04 Thread Matthew Woodcraft
Axel Beckert a...@debian.org wrote: Simon McVittie wrote: Would it be enough for the your old screen binary is /tmp/screen-yhpoe8r/screen notice to also say if your /tmp is mounted noexec, you might need to copy it elsewhere to run it? That's my current plan -- with the noexec notice just

Re: Bug#644788: Bug#654116: RFH: screen -- terminal multiplexor with VT100/ANSI terminal emulation

2012-01-03 Thread Roger Leigh
On Tue, Jan 03, 2012 at 07:17:04AM +0100, Axel Beckert wrote: Hi Yaroslav! Yaroslav Halchenko wrote: I strongly recommend this solution, along with a proper debconf notice. [...] /tmp is a good choice because the next reboot will automatically clean up everything (and obviously

Re: Bug#644788: Bug#654116: RFH: screen -- terminal multiplexor with VT100/ANSI terminal emulation

2012-01-03 Thread Bastian Blank
On Tue, Jan 03, 2012 at 10:05:46AM +, Roger Leigh wrote: If you really need to use a filesystem mounted noexec, just run the binary via /lib/ld.so (you'll need to get the real location from e.g. ldd). Something like: The kernel does not allow executable mappings from noexec filesystems,

Re: Bug#644788: Bug#654116: RFH: screen -- terminal multiplexor with VT100/ANSI terminal emulation

2012-01-03 Thread Yaroslav Halchenko
just thought of it: another possible complication of this approach (mv /usr/bin/screen /tmp/screen-4.0) might be -- tools depending on screen (e.g. byobu) might be in the cold water if the default screen in the PATH cannot do its duties. FWIW: $ apt-cache rdepends screen screen Reverse Depends:

Re: Bug#644788: Bug#654116: RFH: screen -- terminal multiplexor with VT100/ANSI terminal emulation

2012-01-03 Thread Marco d'Itri
On Jan 03, Yaroslav Halchenko deb...@onerussian.com wrote: just thought of it: another possible complication of this approach (mv /usr/bin/screen /tmp/screen-4.0) might be -- tools depending on screen (e.g. byobu) might be in the cold water if the default screen in the PATH cannot do its

Re: Bug#644788: Bug#654116: RFH: screen -- terminal multiplexor with VT100/ANSI terminal emulation

2012-01-03 Thread Axel Beckert
Hi, Roger Leigh wrote: [/tmp mounted noexec] /run/shm (IIRC formerly /dev/shm) likely would be an alternative option, too. No, it would not. This directory is reserved for the eglibc POSIX SHM/SEM interfaces. Thanks for this explanation. It's the first time I read or hear about the

Re: Bug#644788: Bug#654116: RFH: screen -- terminal multiplexor with VT100/ANSI terminal emulation

2012-01-03 Thread Edward Allcutt
On Tue, 3 Jan 2012, Marco d'Itri wrote: It does not matter, this is needed strictly for the time of the upgrade process. Just how short do you expect this to be? I'm sure many of us dist-upgrade daily and (shock! horror!) don't reboot after each upgrade. We also don't expect existing

Re: Bug#644788: Bug#654116: RFH: screen -- terminal multiplexor with VT100/ANSI terminal emulation

2012-01-03 Thread Marco d'Itri
On Jan 03, Axel Beckert a...@debian.org wrote: Thanks for the comment. Cc'ing the relevant bug again, as this is crucial information when I work on fixing the bug. If /tmp is noexec then the administrator mounted it this way and knows about it. So if he is smart enought to mount /tmp noexec

Re: Bug#644788: Bug#654116: RFH: screen -- terminal multiplexor with VT100/ANSI terminal emulation

2012-01-03 Thread Marco d'Itri
On Jan 03, Edward Allcutt edw...@allcutt.me.uk wrote: On Tue, 3 Jan 2012, Marco d'Itri wrote: It does not matter, this is needed strictly for the time of the upgrade process. Just how short do you expect this to be? I'm sure many of us dist-upgrade daily and (shock! horror!) don't reboot

Re: Bug#644788: Bug#654116: RFH: screen -- terminal multiplexor with VT100/ANSI terminal emulation

2012-01-03 Thread Axel Beckert
Hi, Marco d'Itri wrote: If /tmp is noexec then the administrator mounted it this way and knows about it. Yeah, but that is possibly such a long time ago that it's not the first thought. So a small hint to fresh up the memory can't be bad. So if he is smart enought to mount /tmp noexec then

Re: Bug#644788: Bug#654116: RFH: screen -- terminal multiplexor with VT100/ANSI terminal emulation

2012-01-03 Thread Didier Raboud
Le mardi, 3 janvier 2012 16.58:08, Axel Beckert a écrit : Hi, Marco d'Itri wrote: If /tmp is noexec then the administrator mounted it this way and knows about it. Another idea would be to use /usr/bin as temporary place for the old screen. That would be a Policy violation but not a much

Re: Bug#644788: Bug#654116: RFH: screen -- terminal multiplexor with VT100/ANSI terminal emulation

2012-01-03 Thread Marco d'Itri
On Jan 03, Didier Raboud o...@debian.org wrote: 3) In a screen-cleanup init script, test the inexistance of the flag and the existance of /usr/bin/screen-old; in that case, `rm` it. (+ appropriate version and sanity checks, + idempotency) This is bad, because to solve a possible 30

Re: Bug#644788: Bug#654116: RFH: screen -- terminal multiplexor with VT100/ANSI terminal emulation

2012-01-03 Thread Romain Francoise
Yaroslav Halchenko deb...@onerussian.com writes: Thank you Axel for your detailed response and IMHO this is indeed close to an ideal (lightweight, self-cleaning, etc) resolution for this scenario. Of course the real lightweight, self-cleaning solution is to not do anything special as the old

Re: Bug#644788: Bug#654116: RFH: screen -- terminal multiplexor with VT100/ANSI terminal emulation

2012-01-03 Thread Axel Beckert
Hi, Romain Francoise wrote: Thank you Axel for your detailed response and IMHO this is indeed close to an ideal (lightweight, self-cleaning, etc) resolution for this scenario. Of course the real lightweight, self-cleaning solution is to not do anything special as the old binary will be

Re: Bug#644788: Bug#654116: RFH: screen -- terminal multiplexor with VT100/ANSI terminal emulation

2012-01-03 Thread Romain Francoise
Axel Beckert a...@debian.org writes: And I can't really execute it, neither as the user owning the screen session nor as root: ~ # /proc/32039/exe -ls zsh: permission denied: /proc/32039/exe Yes, /proc is mounted noexec so you need to use the ld-linux.so trick. But now that I actually try

Re: Bug#644788: Bug#654116: RFH: screen -- terminal multiplexor with VT100/ANSI terminal emulation

2012-01-02 Thread Henrique de Moraes Holschuh
On Mon, 02 Jan 2012, Karl Goetz wrote: to fix a tiny problem which presents itself just for the length of the upgrade process, if at all. Correct. It's an option nevertheless, so I mentioned it. Sorry if I've misunderstood, but doesn't this problem manifest for *anyone* trying to

Re: Bug#644788: Bug#654116: RFH: screen -- terminal multiplexor with VT100/ANSI terminal emulation

2012-01-02 Thread Axel Beckert
Hi, Romain Francoise wrote: 3) Tell people via the release notes that they should not run the dist-upgrade inside screen, but inside tmux instead. Unfortunately tmux has an issue of its own for squeeze → wheezy upgrades, .oO( Houston, we've got a problem. ) the socket path was

Re: Bug#644788: Bug#654116: RFH: screen -- terminal multiplexor with VT100/ANSI terminal emulation

2012-01-02 Thread Axel Beckert
Hi Julien, Julien Cristau wrote: A) Add an option to screen so the screen client speaks the old protocol to the running server protocol. This IMHO would be best solution and one without a big impact. It's also something which could be Debian-only, i.e. a patch. (It of course

Re: Bug#644788: Bug#654116: RFH: screen -- terminal multiplexor with VT100/ANSI terminal emulation

2012-01-02 Thread Yaroslav Halchenko
On Mon, 02 Jan 2012, Axel Beckert wrote: I strongly recommend this solution, along with a proper debconf notice. [...] /tmp is a good choice because the next reboot will automatically clean up everything (and obviously the old binary will not be needed after a reboot). Thanks for that

Re: Bug#644788: Bug#654116: RFH: screen -- terminal multiplexor with VT100/ANSI terminal emulation

2012-01-02 Thread Karl Goetz
On Mon, 2 Jan 2012 09:40:33 -0200 Henrique de Moraes Holschuh h...@debian.org wrote: On Mon, 02 Jan 2012, Karl Goetz wrote: to fix a tiny problem which presents itself just for the length of the upgrade process, if at all. Correct. It's an option nevertheless, so I mentioned it.

Re: Bug#644788: Bug#654116: RFH: screen -- terminal multiplexor with VT100/ANSI terminal emulation

2012-01-02 Thread Axel Beckert
Hi Yaroslav! Yaroslav Halchenko wrote: I strongly recommend this solution, along with a proper debconf notice. [...] /tmp is a good choice because the next reboot will automatically clean up everything (and obviously the old binary will not be needed after a reboot). Thanks for

Re: Bug#644788: Bug#654116: RFH: screen -- terminal multiplexor with VT100/ANSI terminal emulation

2012-01-01 Thread Axel Beckert
Hi Marco, Marco d'Itri wrote: 1) Let the preinst maintainer script make a copy of the old screen binary, provide a script to clean up this mess afterwards, inform the user via debconf about the issue and his possibilities (where the copy of the old screen is, etc.).

Re: Bug#644788: Bug#654116: RFH: screen -- terminal multiplexor with VT100/ANSI terminal emulation

2012-01-01 Thread Ben Finney
Axel Beckert a...@debian.org writes: A) Add an option to screen so the screen client speaks the old protocol to the running server protocol. This IMHO would be best solution and one without a big impact. It's also something which could be Debian-only, i.e. a patch. (It of course

Re: Bug#644788: Bug#654116: RFH: screen -- terminal multiplexor with VT100/ANSI terminal emulation

2012-01-01 Thread Axel Beckert
Hi Ben, Ben Finney wrote: B) Take care that nobody upgrades the screen package while running inside a screen without being aware of the possible problems. There are few ideas how to implement this: 1) Mention it in the release notes that screen has to be upgraded to the

Re: Bug#644788: Bug#654116: RFH: screen -- terminal multiplexor with VT100/ANSI terminal emulation

2012-01-01 Thread Karl Goetz
On Mon, 2 Jan 2012 04:13:44 +0100 Axel Beckert a...@debian.org wrote: Hi Marco, Marco d'Itri wrote: 2) Make screen 4.0.3 and screen 4.1.0 installable at the same time, i.e. give them different source and binary package names. This would require a great amount of work I fear so,