Re: Switching the default /bin/sh to dash
On Thu, Jun 25, 2009 at 03:42:28PM +0200, Gilles Filippini wrote: Note that /bin/sh belonging to the bash package for now, your changing the symlink will be forgotten if you ever install another version of bash that still has it. Is there any rational for not using the Debian alternatives method? We tried that already 10 years ago. Have a look at this thread: http://www.mail-archive.com/debian-devel@lists.debian.org/msg81293.html The relevant bash version was bash (2.02.1-1.8) unstable; urgency=low * Applied Anthonies patch and recompiled as the libc5 version did not compile for him (closes: #34717, #43050, #43096, #10699). * Bumped the version number of libreadline and recompiled, hopefully in time before the dinstall run ;) -- Torsten Landschoff tors...@debian.org Sat, 18 Sep 1999 19:26:20 +0200 Believe me, using update-alternatives to manage /bin/sh will get you many emails from annoyed users. I think I got around 1000 hate emails on a single day... Greetings, Torsten -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Re: Switching the default /bin/sh to dash
[Giacomo A. Catenazzi] Hmm, so a switch to dash it is not because of POSIX, but because of better code and lighter shell for our scripts? Which is also a good reason for the change. Yes, it is a good change. I would love to switch every installation to dash as /bin/sh, but believe the path of least surprises to the sysadmin is to only change new installations and not existing systems. But could you tell us more about the subtle problems for shutdown sequences. URL: http://bugs.debian.org/159771 is an example, solved by switching from bash to dash. :) Happy hacking, -- Petter Reinholdtsen -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Re: Switching the default /bin/sh to dash
Petter Reinholdtsen wrote: [Giacomo A. Catenazzi] Hmm, so a switch to dash it is not because of POSIX, but because of better code and lighter shell for our scripts? Which is also a good reason for the change. Yes, it is a good change. I would love to switch every installation to dash as /bin/sh, but believe the path of least surprises to the sysadmin is to only change new installations and not existing systems. Right, though how would you implement that? It doesn't look trivial at all to me and will possibly be an extra source of errors. It should also only affect external scripts that are bash specific AFAICS and they would be easily 'fixed' by changing bin/sh to bin/bash in the shebang (can even happen unconditionally). Cheers Luk -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Re: Switching the default /bin/sh to dash
Raphael Hertzog wrote: On Thu, 25 Jun 2009, Raphael Geissert wrote: Artur R. Czechowski wrote: What about debconf question? dash already has one, the idea is to make it essential and default to yes, so that as soon as it is installed the symlink is changed. If you wish to have dash installed but not as /bin/sh you can always dpkg-reconfigure dash. Hum, AFAIK if it defaults to yes, it will be changed on upgrade for anyone who has not yet seen the question. So that doesn't work if your plan is to not change it except for new installations. I've not seen any response to this, but it seems to me to be a very valid point. dash currently is optional, so there will be on a lot of existing systems on which it is not installed. How is the planned strategy going to prevent dash becoming the default shell on existing systems when it gets installed for the first time because of its raised priority? -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Re: Switching the default /bin/sh to dash
Frans Pop wrote: Raphael Hertzog wrote: Hum, AFAIK if it [debconf prompt] defaults to yes, it will be changed on upgrade for anyone who has not yet seen the question. So that doesn't work if your plan is to not change it except for new installations. I've not seen any response to this, but it seems to me to be a very valid point. I though I had replied, sorry. dash currently is optional, so there will be on a lot of existing systems on which it is not installed. How is the planned strategy going to prevent dash becoming the default shell on existing systems when it gets installed for the first time because of its raised priority? There are two, both ugly actually, ways to do it: a) by making dpkg pre-depend on dash so that it is installed and can see if an older dpkg is installed b) by finding a file that could tell us the installation date and base the decision on that. I've personally had no time to check if there's any file installed by dpkg that could indicate the installation date. But another option, as some people have already expressed, is to simply make the change on all the installations. Unless somebody knows a file that could be used to do it the b) way I guess I won't have another option but to send another proposal stating that all the installations would be modified. In case the reasons are not obvious enough, a D-I-based solution is not a candidate as newly created chroots (debootstrap-created) should get dash and not bash. Cheers, Raphael Geissert -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Re: Switching the default /bin/sh to dash
Raphael Geissert wrote: dash currently is optional, so there will be on a lot of existing systems on which it is not installed. How is the planned strategy going to prevent dash becoming the default shell on existing systems when it gets installed for the first time because of its raised priority? There are two, both ugly actually, ways to do it: a) by making dpkg pre-depend on dash so that it is installed and can see if an older dpkg is installed b) by finding a file that could tell us the installation date and base the decision on that. An alternative that is still not pretty, but at least keeps the ugliness in the packages related to the switch and is fairly straightforward to implement, would be to make the new dash pre-depend on a new version of bash and have the maintainer scripts of bash preseed the dash template to false if: - bash is being upgraded - the dash template does not yet exist Cheers, FJP -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Re: Switching the default /bin/sh to dash
Frans Pop wrote: An alternative that is still not pretty, but at least keeps the ugliness in the packages related to the switch and is fairly straightforward to implement, would be to make the new dash pre-depend on a new version of bash and have the maintainer scripts of bash preseed the dash template bash playing the evil role, trying to keep some users for himself :) to false if: - bash is being upgraded - the dash template does not yet exist It's another option, yes. Will wait some more feedback, though. Cheers, Raphael Geissert -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Re: Switching the default /bin/sh to dash
Russ Allbery wrote: Giacomo A. Catenazzi c...@debian.org writes: PS: I think that dash is a step toward a truly posix shell, but it is not yet a posix shell: we still need fewer extentions. So in five/ten year we will change it again. I doubt that we're going to move in that direction farther than where dash already is. The extensions that are left in dash are by and large things that people really want to use and that are helpful in practical ways for writing reasonable scripts. I think it's more likely that POSIX will end up adopting some of those extensions. (I certainly hope this will happen for things like test -a.) I also hope so. Anyway I was thinking about echo -n, which IMHO requires a such step (and in this case I don't think POSIX will restore the old behaviour). A silent change will break a lot of sysadmin scripts. ciao cate -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Re: Switching the default /bin/sh to dash
Steve Langasek wrote: On Wed, Jun 24, 2009 at 10:21:45PM -0500, Raphael Geissert wrote: I just noticed I forgot to say something: What won't change: * Bash will still be used as the default interactive shells for users * the sh symlink won't be modified on existing installations I understand the concerns about not breaking existing scripts, but I'll nevertheless be disappointed if this switch isn't made on upgrades as well. Using bash as /bin/sh causes a number of subtle problems for shutdown sequences, in addition to the obvious performance issues, and I think the fix for non-POSIX shell scripts is straightforward enough that we should just document the change (in the release notes and NEWS.Debian) and tell users to use the right interpreter if they have any doubts about their dash-compatibility. Hmm, so a switch to dash it is not because of POSIX, but because of better code and lighter shell for our scripts? Which is also a good reason for the change. But could you tell us more about the subtle problems for shutdown sequences. The bash can simulate the init program, which is very good for system management on emergencies or debug the init procedure. (I don't know about dash) These are special cases, but it would nice if we support or document the strange iterations of bash (and maybe also of busibox) on init procedures. ciao cate -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Re: Switching the default /bin/sh to dash
Raphael Geissert wrote: dash already has one, the idea is to make it essential and default to yes, so that as soon as it is installed the symlink is changed. If you wish to have dash installed but not as /bin/sh you can always dpkg-reconfigure dash. Why essential? It doesn't provide anything dash-specific, and I hope nobody will write a script starting with #!/bin/dash. I prefer that we handle it like the libraries: make it essential-like via dependencies of true-essential packages. ciao cate PS: I think that dash is a step toward a truly posix shell, but it is not yet a posix shell: we still need fewer extentions. So in five/ten year we will change it again. -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Re: Switching the default /bin/sh to dash
Quoting Luk Claes (l...@debian.org): It's enough to dpkg-reconfigure dash for existing installations. And, by the way, if the switch happens, one has to think about rewording the current debconf template for dash, that says: Description: Install dash as /bin/sh? The default /bin/sh shell on Debian and Debian-based systems is bash. . However, since the default shell is required to be POSIX-compliant, any shell that conforms to POSIX, such as dash, can serve as /bin/sh. You may wish to do this because dash is faster and smaller than bash. If dash becomes the default /bin/sh, then that template should be kept with a different wording (for those who might want to restore it as the default sh) and a similar template (and maintainer script magic) should be added to bash. signature.asc Description: Digital signature
Re: Switching the default /bin/sh to dash
Giacomo A. Catenazzi c...@debian.org writes: PS: I think that dash is a step toward a truly posix shell, but it is not yet a posix shell: we still need fewer extentions. So in five/ten year we will change it again. I doubt that we're going to move in that direction farther than where dash already is. The extensions that are left in dash are by and large things that people really want to use and that are helpful in practical ways for writing reasonable scripts. I think it's more likely that POSIX will end up adopting some of those extensions. (I certainly hope this will happen for things like test -a.) -- Russ Allbery (r...@debian.org) http://www.eyrie.org/~eagle/ -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Re: Switching the default /bin/sh to dash
On Wed, Jun 24, 2009 at 10:21:45PM -0500, Raphael Geissert wrote: I just noticed I forgot to say something: What won't change: * Bash will still be used as the default interactive shells for users * the sh symlink won't be modified on existing installations I understand the concerns about not breaking existing scripts, but I'll nevertheless be disappointed if this switch isn't made on upgrades as well. Using bash as /bin/sh causes a number of subtle problems for shutdown sequences, in addition to the obvious performance issues, and I think the fix for non-POSIX shell scripts is straightforward enough that we should just document the change (in the release notes and NEWS.Debian) and tell users to use the right interpreter if they have any doubts about their dash-compatibility. We certainly make much more intrusive changes to the implementations of other interpreters across releases, and while none of these have quite the same penetration as /bin/sh, I think weighing the scope of the changes vs. the number of scripts puts this on the same order as past updates to /usr/bin/perl or /usr/bin/python. -- Steve Langasek Give me a lever long enough and a Free OS Debian Developer to set it on, and I can move the world. Ubuntu Developerhttp://www.debian.org/ slanga...@ubuntu.com vor...@debian.org -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Re: Switching the default /bin/sh to dash
On Thu, Jun 25, 2009 at 07:31:15AM +0200, Mike Hommey wrote: On Thu, Jun 25, 2009 at 06:47:07AM +0200, Hendrik Sattler wrote: Am Donnerstag 25 Juni 2009 05:21:45 schrieb Raphael Geissert: I just noticed I forgot to say something: What won't change: * Bash will still be used as the default interactive shells for users * the sh symlink won't be modified on existing installations [cut] I'd say if /bin/sh points to the current default (/bin/bash), then it should be modified. OTOH, if it was modified locally by the admin to point somewhere else, leave it alone. What about debconf question? Regards Artur -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Re: Switching the default /bin/sh to dash
Mike Hommey m...@glandium.org writes: I'd say if /bin/sh points to the current default (/bin/bash), then it should be modified. OTOH, if it was modified locally by the admin to point somewhere else, leave it alone. That would potentially break locally written or installed scripts. Not touching the /bin/sh link on upgrade seems less harmful. -- Stig Sandbeck Mathisen -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Re: Switching the default /bin/sh to dash
Quoting Raphael Geissert (atom...@gmail.com): Switch the default /bin/sh to dash in the following weeks /me applauses (I'm using dash as /bin/sh for about NN years now: IIRC I switched after Marga's work in the GSOC about the boot process speed up) signature.asc Description: Digital signature
Re: Switching the default /bin/sh to dash
On Thu, Jun 25, 2009 at 12:10:46AM -0500, Raphael Geissert wrote:
And so that all users that upgrade do not benefit from the goal of this
change? Even better.
This is to avoid causing undesirable effects when upgrading. People have
always been concerned about such kind of changes, and they are more than
right. The goal is not to cause a chaos.
I can understand the fear.
Still, as a DD, I would like to explicitly switch to dash to help in
spotting possible problems. Can you please consider document how to
switch? I guess switching the symlink is enough, but an entry in
README.Debian saying explicitly so (and possibly documenting extra
needed steps) would be nice.
Thanks for your work!
Cheers.
--
Stefano Zacchiroli -o- PhD in Computer Science \ PostDoc @ Univ. Paris 7
z...@{upsilon.cc,pps.jussieu.fr,debian.org} -- http://upsilon.cc/zack/
Dietro un grande uomo c'è ..| . |. Et ne m'en veux pas si je te tutoie
sempre uno zaino ...| ..: | Je dis tu à tous ceux que j'aime
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Re: Switching the default /bin/sh to dash
On Wed, 24 Jun 2009 17:51:58 -0500, Raphael Geissert atom...@gmail.com wrote: Side effects: * Errors caused by the use of bashisms. * Faster boot, builds, and general usage of /bin/sh scripts. * Reduced memory footprint when running /bin/sh scripts. Counter side effects: * During the following weeks I will be working on providing patches for the known issues (check the list at [1]), * and performing another archive-wide checkbashisms check on binary packages, * debian/rules, * and then an archive rebuild with dash as /bin/sh should follow. Do you have statistics about how many packages would be instantly RC buggy because they have #!/bin/bash scripts and would now need to depend or even pre-depend on bash? Since bash is essential, it is a bug to explicitly depend on bash, and after the change it will be a bug to not depend on bash. Greetings Marc -- -- !! No courtesy copies, please !! - Marc Haber |Questions are the | Mailadresse im Header Mannheim, Germany | Beginning of Wisdom | http://www.zugschlus.de/ Nordisch by Nature | Lt. Worf, TNG Rightful Heir | Fon: *49 621 72739834 -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Re: Switching the default /bin/sh to dash
On 25/06/09 at 10:05 +0200, Marc Haber wrote: On Wed, 24 Jun 2009 17:51:58 -0500, Raphael Geissert atom...@gmail.com wrote: Side effects: * Errors caused by the use of bashisms. * Faster boot, builds, and general usage of /bin/sh scripts. * Reduced memory footprint when running /bin/sh scripts. Counter side effects: * During the following weeks I will be working on providing patches for the known issues (check the list at [1]), * and performing another archive-wide checkbashisms check on binary packages, * debian/rules, * and then an archive rebuild with dash as /bin/sh should follow. Do you have statistics about how many packages would be instantly RC buggy because they have #!/bin/bash scripts and would now need to depend or even pre-depend on bash? Since bash is essential, it is a bug to explicitly depend on bash, and after the change it will be a bug to not depend on bash. It won't: bash stays the default shell for interactive use, so it stays essential as well. -- | Lucas Nussbaum | lu...@lucas-nussbaum.net http://www.lucas-nussbaum.net/ | | jabber: lu...@nussbaum.fr GPG: 1024D/023B3F4F | -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Re: Switching the default /bin/sh to dash
On 2009-06-25 10:05 +0200, Marc Haber wrote: Do you have statistics about how many packages would be instantly RC buggy because they have #!/bin/bash scripts and would now need to depend or even pre-depend on bash? Since bash is essential, it is a bug to explicitly depend on bash, and after the change it will be a bug to not depend on bash. I don't think that Raphael meant to make bash non-essential. Sven -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Re: Switching the default /bin/sh to dash
Hi, On Wed, 24 Jun 2009 17:51:58 -0500 Raphael Geissert atom...@gmail.com wrote: Hello everybody, I think everyone readying this list is more than aware of the intention to switch to dash as the default /bin/sh. A lot of work has been done on many sides to make this switch doable and as smooth as possible and plenty of people has been contributing by testing, filing bugs, providing patches, fixing bugs and by using dash. [...] * and performing another archive-wide checkbashisms check on binary Checkbashisms is a lintian check, right? Can I use it to check my own scripts, not being in a package? Cheers, harry signature.asc Description: PGP signature
Re: Switching the default /bin/sh to dash
On 25/06/09 at 10:32 +0200, Harald Braumann wrote: Hi, On Wed, 24 Jun 2009 17:51:58 -0500 Raphael Geissert atom...@gmail.com wrote: Hello everybody, I think everyone readying this list is more than aware of the intention to switch to dash as the default /bin/sh. A lot of work has been done on many sides to make this switch doable and as smooth as possible and plenty of people has been contributing by testing, filing bugs, providing patches, fixing bugs and by using dash. [...] * and performing another archive-wide checkbashisms check on binary Checkbashisms is a lintian check, right? No, it's in devscripts. -- | Lucas Nussbaum | lu...@lucas-nussbaum.net http://www.lucas-nussbaum.net/ | | jabber: lu...@nussbaum.fr GPG: 1024D/023B3F4F | -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Re: Switching the default /bin/sh to dash
Stefano Zacchiroli z...@debian.org (25/06/2009): Still, as a DD, I would like to explicitly switch to dash to help in spotting possible problems. Can you please consider document how to switch? I guess switching the symlink is enough, but an entry in README.Debian saying explicitly so (and possibly documenting extra needed steps) would be nice. Note that /bin/sh belonging to the bash package for now, your changing the symlink will be forgotten if you ever install another version of bash that still has it. Mraw, KiBi. signature.asc Description: Digital signature
Re: Switching the default /bin/sh to dash
Lucas Nussbaum lu...@lucas-nussbaum.net (25/06/2009): On 25/06/09 at 10:32 +0200, Harald Braumann wrote: Checkbashisms is a lintian check, right? No, it's in devscripts. Yes, it is also a lintian check. Although not as complete, see lintian's check/scripts file. Mraw, KiBi. signature.asc Description: Digital signature
Re: Switching the default /bin/sh to dash
Cyril Brulebois wrote, Thu, 25 Jun 2009 14:51:46 +0200: Lucas Nussbaum lu...@lucas-nussbaum.net (25/06/2009): On 25/06/09 at 10:32 +0200, Harald Braumann wrote: Checkbashisms is a lintian check, right? No, it's in devscripts. Yes, it is also a lintian check. Although not as complete, see lintian's check/scripts file. For completeness... checkbashisms started life as basically a copy of the relevant section of checks/scripts and the two then developed separately. More recently there's been a crossover between devscripts and Lintian maintainership (i.e. me) so they've become much more closely synced. I tend to apply obvious fixes to both and let newer or more FP-prone features mature in checkbashisms for a bit before adding them to Lintian. Adam -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Re: Switching the default /bin/sh to dash
Cyril Brulebois a écrit : Stefano Zacchiroli z...@debian.org (25/06/2009): Still, as a DD, I would like to explicitly switch to dash to help in spotting possible problems. Can you please consider document how to switch? I guess switching the symlink is enough, but an entry in README.Debian saying explicitly so (and possibly documenting extra needed steps) would be nice. Note that /bin/sh belonging to the bash package for now, your changing the symlink will be forgotten if you ever install another version of bash that still has it. Is there any rational for not using the Debian alternatives method? Thanks, _Gilles. -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Re: Switching the default /bin/sh to dash
On 2009-06-25 14:40 +0200, Cyril Brulebois wrote: Stefano Zacchiroli z...@debian.org (25/06/2009): Still, as a DD, I would like to explicitly switch to dash to help in spotting possible problems. Can you please consider document how to switch? I guess switching the symlink is enough, but an entry in README.Debian saying explicitly so (and possibly documenting extra needed steps) would be nice. Note that /bin/sh belonging to the bash package for now, your changing the symlink will be forgotten if you ever install another version of bash that still has it. Therefore one has to use dpkg-divert to move this symlink out of the way, which is achieved most easily by dpkg-reconfigure dash. Sven -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Re: Switching the default /bin/sh to dash
Le jeudi 25 juin 2009 à 15:42 +0200, Gilles Filippini a écrit : Cyril Brulebois a écrit : Note that /bin/sh belonging to the bash package for now, your changing the symlink will be forgotten if you ever install another version of bash that still has it. Is there any rational for not using the Debian alternatives method? IIRC, when using alternatives, there is no guarantee that the alternative is always usable. For something as critical as /bin/sh, it does not sound like a good idea. -- .''`. Josselin Mouette : :' : `. `' “I recommend you to learn English in hope that you in `- future understand things” -- Jörg Schilling signature.asc Description: Ceci est une partie de message numériquement signée
Re: Switching the default /bin/sh to dash
Artur R. Czechowski wrote: What about debconf question? dash already has one, the idea is to make it essential and default to yes, so that as soon as it is installed the symlink is changed. If you wish to have dash installed but not as /bin/sh you can always dpkg-reconfigure dash. Cheers, Raphael Geisser -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Re: Switching the default /bin/sh to dash
Stefano Zacchiroli wrote: On Thu, Jun 25, 2009 at 12:10:46AM -0500, Raphael Geissert wrote: And so that all users that upgrade do not benefit from the goal of this change? Even better. This is to avoid causing undesirable effects when upgrading. People have always been concerned about such kind of changes, and they are more than right. The goal is not to cause a chaos. I can understand the fear. Still, as a DD, I would like to explicitly switch to dash to help in spotting possible problems. Can you please consider document how to switch? I guess switching the symlink is enough, but an entry in README.Debian saying explicitly so (and possibly documenting extra needed steps) would be nice. It's enough to dpkg-reconfigure dash for existing installations. Cheers Luk -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Re: Switching the default /bin/sh to dash
Adam D. Barratt a...@adam-barratt.org.uk writes: For completeness... checkbashisms started life as basically a copy of the relevant section of checks/scripts and the two then developed separately. More recently there's been a crossover between devscripts and Lintian maintainership (i.e. me) so they've become much more closely synced. I tend to apply obvious fixes to both and let newer or more FP-prone features mature in checkbashisms for a bit before adding them to Lintian. The long-term goal is to turn checkbashisms into some more convenient sort of shared code that both Lintian and the devscripts check can use. Currently, Lintian only checks maintainer scripts, so you should use checkbashisms to check other scripts. Checking other scripts and debian/rules files has been on the wish list for quite a while, but as yet we've not done the necessary work in Lintian. -- Russ Allbery (r...@debian.org) http://www.eyrie.org/~eagle/ -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Re: Switching the default /bin/sh to dash
On Thu, 25 Jun 2009, Raphael Geissert wrote: Artur R. Czechowski wrote: What about debconf question? dash already has one, the idea is to make it essential and default to yes, so that as soon as it is installed the symlink is changed. If you wish to have dash installed but not as /bin/sh you can always dpkg-reconfigure dash. Hum, AFAIK if it defaults to yes, it will be changed on upgrade for anyone who has not yet seen the question. So that doesn't work if your plan is to not change it except for new installations. Cheers, -- Raphaël Hertzog Contribuez à Debian et gagnez un cahier de l'admin Debian Lenny : http://www.ouaza.com/wp/2009/03/02/contribuer-a-debian-gagner-un-livre/ -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Re: Switching the default /bin/sh to dash
Raphael Geissert wrote: Hello everybody, I think everyone readying this list is more than aware of the intention to switch to dash as the default /bin/sh. Summarising: Unless a major blocker shows up, the switch is going to be done on the following weeks. \o/, finally. Thanks for all your hard work, Michael -- Why is it that all of the instruments seeking intelligent life in the universe are pointed away from Earth? signature.asc Description: OpenPGP digital signature
Re: Switching the default /bin/sh to dash
On Wed, Jun 24, 2009 at 05:51:58PM -0500, Raphael Geissert wrote: Side effects: * Errors caused by the use of bashisms. And the really important side-effect is that user scripts on all sorts of installed systems could experience trouble. * Faster boot, builds, and general usage of /bin/sh scripts. That could be accomplished by just setting the bangpath different, right? * Reduced memory footprint when running /bin/sh scripts. That's a nice thing. Both of these are nice to have, of course, but we need to make sure this is documented explicitly, well, and in BIG UPPERCASE LETTERS in the release notes. This could be a significant issue at companies that have done a lot of scripting outside the archive. * It's been more than three years since Ubuntu made the switch, without all the extra bashisms-hunting Debian has done, without rolling it back. Not necessarily relevant. They have a reputation (whether deserved or not is a different discussion) of breaking people's machines on upgrade, and don't have the server penetration Debian does either. -- John -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Re: Switching the default /bin/sh to dash
Hi, I just noticed I forgot to say something: What won't change: * Bash will still be used as the default interactive shells for users * the sh symlink won't be modified on existing installations Cheers, Raphael Geissert -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Re: Switching the default /bin/sh to dash
John Goerzen wrote: On Wed, Jun 24, 2009 at 05:51:58PM -0500, Raphael Geissert wrote: Side effects: * Errors caused by the use of bashisms. And the really important side-effect is that user scripts on all sorts of installed systems could experience trouble. You are right, you made me notice I forgot to mention something: * the sh symlink won't be modified on existing installations * Faster boot, builds, and general usage of /bin/sh scripts. That could be accomplished by just setting the bangpath different, right? Of every single /bin/sh script? sure * Reduced memory footprint when running /bin/sh scripts. That's a nice thing. Both of these are nice to have, of course, but we need to make sure this is documented explicitly, well, and in BIG UPPERCASE LETTERS in the release notes. This could be a significant issue at companies that have done a lot of scripting outside the archive. Of course this is going to be mentioned on the release notes (just like the switch to rsyslog as the default syslogd); but like I just said, the change will only immediately affect new installations. * It's been more than three years since Ubuntu made the switch, without all the extra bashisms-hunting Debian has done, without rolling it back. Not necessarily relevant. They have a reputation (whether deserved or not is a different discussion) of breaking people's machines on upgrade, and don't have the server penetration Debian does either. It's relevant in the sense that * we are not making a never done before move, * many issues have been fixed because of their change, * many upstreams are now aware of bashisms. I won't object any of your other statements, but in this case we are not discussing if what Ubuntu did was right or wrong, nor anything else. And as such, what matters is that they made the move and it has worked for over three years. Thanks for your comments, and I hope that with the extra clarification I've addressed your concerns. Cheers, Raphael Geissert -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Re: Switching the default /bin/sh to dash
Am Donnerstag 25 Juni 2009 05:21:45 schrieb Raphael Geissert: I just noticed I forgot to say something: What won't change: * Bash will still be used as the default interactive shells for users * the sh symlink won't be modified on existing installations So that it will be even more strange that a script with bashisms works on some Debian Squeeze systems but not on others? Yeah, great idea. And so that all users that upgrade do not benefit from the goal of this change? Even better. I usually don't like those not-on-upgrade exceptions. HS -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Re: Switching the default /bin/sh to dash
Hendrik Sattler wrote: Am Donnerstag 25 Juni 2009 05:21:45 schrieb Raphael Geissert: I just noticed I forgot to say something: What won't change: * Bash will still be used as the default interactive shells for users * the sh symlink won't be modified on existing installations So that it will be even more strange that a script with bashisms works on some Debian Squeeze systems but not on others? Yeah, great idea. reportbug indicates what /bin/sh points to, and it should be irrelevant, since many people have been using all sort of shell interpreters as /bin/sh for many many years. And so that all users that upgrade do not benefit from the goal of this change? Even better. This is to avoid causing undesirable effects when upgrading. People have always been concerned about such kind of changes, and they are more than right. The goal is not to cause a chaos. I usually don't like those not-on-upgrade exceptions. I'd prefer if comments were restricted to objective arguments and not subjective; specially when they include unneeded sarcasm. Regards, Raphael Geissert -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Re: Switching the default /bin/sh to dash
On Thu, Jun 25, 2009 at 06:47:07AM +0200, Hendrik Sattler wrote: Am Donnerstag 25 Juni 2009 05:21:45 schrieb Raphael Geissert: I just noticed I forgot to say something: What won't change: * Bash will still be used as the default interactive shells for users * the sh symlink won't be modified on existing installations So that it will be even more strange that a script with bashisms works on some Debian Squeeze systems but not on others? Yeah, great idea. And so that all users that upgrade do not benefit from the goal of this change? Even better. I usually don't like those not-on-upgrade exceptions. I'd say if /bin/sh points to the current default (/bin/bash), then it should be modified. OTOH, if it was modified locally by the admin to point somewhere else, leave it alone. Mike -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Re: Switching the default /bin/sh to dash
On Thu, 2009-06-25 at 06:47 +0200, Hendrik Sattler wrote: Am Donnerstag 25 Juni 2009 05:21:45 schrieb Raphael Geissert: I just noticed I forgot to say something: (BTW, scripts not only loads faster under dash, they also run faster in Dash.) What won't change: * Bash will still be used as the default interactive shells for users * the sh symlink won't be modified on existing installations So that it will be even more strange that a script with bashisms works on some Debian Squeeze systems but not on others? Upgraded systems don't behave exactly like new systems, this isn't specific for Debian. The release notes can document those changed behaviors, isn't it? (the NEWS.Debian too) And every one RTFM. And so that all users that upgrade do not benefit from the goal of this change? This is the difference between upgrading a system, and installing a new system: When upgrading a system, you want your existing applications to keep working the same way, so you prefer to keep the backward compatible way (see John Goerzen's concerns about entreprise-made shell scripts). On the other hand, when an application is installed [on a fresh system], it is ok to introduce new behavior, since it is much more easier to detect incompatible scripts as you write/install them. I usually don't like those not-on-upgrade exceptions. FYI, I have worked on modular tool (a Posix script;), that can test and warn such changes on upgraded systems. I would a test for [bd]ash. http://wiki.debian.org/UpgradeAdvisor Regards, Franklin -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Re: Switching the default /bin/sh to dash
Mike Hommey wrote: On Thu, Jun 25, 2009 at 06:47:07AM +0200, Hendrik Sattler wrote: Am Donnerstag 25 Juni 2009 05:21:45 schrieb Raphael Geissert: I just noticed I forgot to say something: What won't change: * Bash will still be used as the default interactive shells for users * the sh symlink won't be modified on existing installations So that it will be even more strange that a script with bashisms works on some Debian Squeeze systems but not on others? Yeah, great idea. And so that all users that upgrade do not benefit from the goal of this change? Even better. I usually don't like those not-on-upgrade exceptions. I'd say if /bin/sh points to the current default (/bin/bash), then it should be modified. OTOH, if it was modified locally by the admin to point somewhere else, leave it alone. How do you make the difference between an administrator choosing for the default and one choosing for bash specifically? I think it's best to either leave it alone (preferred option) or ask the administrator (using debconf) if he wants to change to the default. In any case it should be mentioned in the Release Notes and other documentation regarding Squeeze. Cheers Luk -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
