Re: [arch-general] [Bulk] Re: A good time to switch to dash as /bin/sh?
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On 09/28/2014 07:04 AM, Benjamin A. Shelton wrote: On 09/27/2014 02:13 AM, Ralf Mardorf wrote: On Sat, 2014-09-27 at 10:02 +0200, Florian Pelz wrote: Same here. With only NoExtract, I linked /bin/sh to dash, reinstalled bash, and /bin/sh was gone. With both NoExtract and NoUpgrade, I did the same and /bin/sh was still a link to dash. My bad, until now I'm using NoExtract for files I don't want to have, I wasn't aware that a file or link we want to have gets lost. Okay, so I wasn't *completely* losing my mind (what little of it there is!). Here's what I think is happening (probably wrong, but this is what I've deduced from further reading and some strace fun): Since (re)installing over an existing package first removes its constituent files, NoExtract alone results in the reinstallation process removing bash (and the /usr/bin/sh link). But, since the file is specified as NoExtract, the link/file isn't recreated during package extraction (it's skipped). NoUpgrade, on the other hand, prevents the file from being removed (reinstallation must therefore be considered as an upgrade for this purpose) but if it's not also specified by NoExtract, it's immediately overwritten by the new copy. So, if my understanding is correct, this would explain why both options must be used in order to keep something relatively unscathed. NoUpgrade prevents its removal (or more accurately it prevents its upgrade); NoExtract prevents it from being overwritten. Disclaimer: I haven't looked at the pacman sources yet. This is exclusively from observation and what my (admittedly very limited) understanding of pacman provides. Benjamin That makes sense, even if it is not what I would have expected pacman to do judging from the description in man pacman.conf. Thank you. -BEGIN PGP SIGNATURE- Version: GnuPG v2 iQIcBAEBAgAGBQJUJ6iJAAoJEMqreLELZNG3wSMP/1zge+KR4yRSi/ZZUTILsqGO 8E6DfmHDfvOvLZddTTiSGmSJm8NV1j4kjjon6ifuW2orEBmd/Hr4L22bCGQrd8X6 oWseS0VoXgxMRmjO/CPKImvOUY3kMmBEYZzV56Ags6iCBQrXo0fkFrg4Gy65+lYc JIH2nnKQLCb5D0JMfcdnicrmTwitqWDPSoE/rbgKpa4bLG/WzvZTClJBP9wOtlaI aWNEUSoEYiXaz2/p9HoEzWGTY22IAz01eVY/PfV0J7nY6h+N2evas+T9Z1Cq3W3D KPJgqjiCSh2f02Sr+iERWl71E5hOEQLQb+b1vI4HsZShwlwpdpRSPbWdiUB878fI pZM8lMURK3yt2nLc5tQ6tcUDmMskcWt/RXw/gLTdDfURGfeymD9362BQPR6tu5/P WxFQekf+ScODStOFU98DUASo7gRdR30+WvVzUwpuAoent/fgLNEQvOX7r8uYX4DT 7RVnmLO2u6SoPD08Xlocd18qqc8EIZJm/lCKzwX/drF7+KKMxVe/vKKzPeGbHhhb gr657+6W3xZBYtSmBvabjq8Tktp/TvLfxiSUGdCxfCSqLqw+hs5UYXNxKAx6GvdT RlX6rlPaylX5cBPWoB1Jt+1fDuTZPZnsMDiYDF0GdCI8P68+zijrmJ9vkXEkF/cj tcdta/fK8ceZogIN/i0Y =R4dC -END PGP SIGNATURE-
Re: [arch-general] [Bulk] Re: A good time to switch to dash as /bin/sh?
On Sat, 2014-09-27 at 09:04 +0200, Florian Pelz wrote: On 09/27/2014 09:01 AM, Benjamin A. Shelton wrote: On 09/26/2014 05:11 PM, Doug Newgard wrote: I should qualify that in that I don't think adding another package to base is a good idea *unless* there is a significant benefit to doing so. The plan to add dash to base when Arch was using initscripts made sense, it doesn't now that we're using systemd. There's already too much in base IMO. Doug By that reasoning, if the intent is to make base leaner, then bash ought to be replaced with dash (mkinitcpio and others notwithstanding). :) Benjamin Regardless of what's the default, could there be a cleaner way to use dash as one's /bin/sh without preventing pacman from upgrading bash? I would add usr/bin/sh to my pacman.conf's NoExtract, then bash would be updated, but the link wouldn't be overwritten, I'm already using it for other reasons: [rocketmouse@archlinux ~]$ pacman -Ql bash | grep /usr/bin/sh bash /usr/bin/sh [rocketmouse@archlinux ~]$ grep NoExtract /etc/pacman.conf NoExtract = usr/share/xsessions/gnome.desktop usr/share/xsessions/gnome-fallback.desktop usr/share/xsessions/gnome-flashback-compiz.desktop usr/share/xsessions/openbox-kde.desktop
Re: [arch-general] [Bulk] Re: A good time to switch to dash as /bin/sh?
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On 09/27/2014 09:23 AM, Ralf Mardorf wrote: On Sat, 2014-09-27 at 09:04 +0200, Florian Pelz wrote: On 09/27/2014 09:01 AM, Benjamin A. Shelton wrote: On 09/26/2014 05:11 PM, Doug Newgard wrote: I should qualify that in that I don't think adding another package to base is a good idea *unless* there is a significant benefit to doing so. The plan to add dash to base when Arch was using initscripts made sense, it doesn't now that we're using systemd. There's already too much in base IMO. Doug By that reasoning, if the intent is to make base leaner, then bash ought to be replaced with dash (mkinitcpio and others notwithstanding). :) Benjamin Regardless of what's the default, could there be a cleaner way to use dash as one's /bin/sh without preventing pacman from upgrading bash? I would add usr/bin/sh to my pacman.conf's NoExtract, then bash would be updated, but the link wouldn't be overwritten, I'm already using it for other reasons: [rocketmouse@archlinux ~]$ pacman -Ql bash | grep /usr/bin/sh bash /usr/bin/sh [rocketmouse@archlinux ~]$ grep NoExtract /etc/pacman.conf NoExtract = usr/share/xsessions/gnome.desktop usr/share/xsessions/gnome-fallback.desktop usr/share/xsessions/gnome-flashback-compiz.desktop usr/share/xsessions/openbox-kde.desktop Thank you. I probably should pay more attention to what the ArchWiki says on dash; I just read it there. -BEGIN PGP SIGNATURE- Version: GnuPG v2 iQIcBAEBAgAGBQJUJmbSAAoJEMqreLELZNG3e3QQAKsXEXJtdRKkDdryWp9N/qaN gI7JgVl5IXhhz6rxes7AdC4uSxJ58otmD4xvORU/jyU9crI/5EdGdosFbcX/LMub x5JxxWcskcFfaL2RLW4LV4AU0Ec7Vllut03TVAYiQDGE0D9bXYntymtBQc6vuvIo xhln8h9c1O8CnwsDdmCX/PqaprEXB4YKDoK2jShlbzs7kKv0fx/1EHC1IEfglu9R tMChMkyFwcIvyH1dVNqVIaIt0TlQsjcbxRxhddmuZX2hriX3fzFQkywdxva8Pm+o 9I1tfz7CJ8HDxPo9WB5iaeE5PXPyUZRh5H/CNCFRmyb88BuYs6ZG+HyKrmrX074d AkKGS9A856ryemFX437NuUmWdnziJqJqkAbN6L06FHzFX+/rPzg5pJQD2ctVUDT3 Zv3DUgVhLQcgtEKxVKsI8YBHOM7A0EVRh62KFAaTzNfFbRNVj6eLnK0GPqQDrcL7 lLBUdUGxCvVQ/3q7hbrLFg1kDqu2sH5ZsJlV53C+JwwSLDx5K6zwDoGQ5fpT3j21 klWYeDWcdh1aKGDr8ufU0Y6jtwOUkIkx+BFCz3+hg9LM3xkEnxpc4vTZ9gppa1fG v5QvNzG7gmguJghEJ0OcGZ6lkHr4IkwXtAA9qSFCxLDsQmbVEplpaLMgTrFb5LZW hDuNeiw0xMpQzchAuknU =Gjur -END PGP SIGNATURE-
Re: [arch-general] [Bulk] Re: A good time to switch to dash as /bin/sh?
On Sat, 2014-09-27 at 10:02 +0200, Florian Pelz wrote: On 09/27/2014 09:30 AM, Benjamin A. Shelton wrote: On 09/27/2014 01:28 AM, Ralf Mardorf wrote: On Sat, 2014-09-27 at 01:21 -0600, Benjamin A. Shelton wrote: I assumed NoExtract should have been enough Correct! Or are we missing something? Oddly, using only NoExtract caused pacman to remove the usr/bin/sh symlink, replacing it with nothing. (Using both NoUpgrade and NoExtract seems to work fine.) Perhaps it's a local oddity on my installation, but I admit I didn't fiddle with it for more than 5 minutes. I very likely overlooked something. ...when all you have is a hammer... Benjamin Same here. With only NoExtract, I linked /bin/sh to dash, reinstalled bash, and /bin/sh was gone. With both NoExtract and NoUpgrade, I did the same and /bin/sh was still a link to dash. My bad, until now I'm using NoExtract for files I don't want to have, I wasn't aware that a file or link we want to have gets lost.
Re: [arch-general] [Bulk] Re: A good time to switch to dash as /bin/sh?
On 09/27/2014 02:13 AM, Ralf Mardorf wrote: On Sat, 2014-09-27 at 10:02 +0200, Florian Pelz wrote: Same here. With only NoExtract, I linked /bin/sh to dash, reinstalled bash, and /bin/sh was gone. With both NoExtract and NoUpgrade, I did the same and /bin/sh was still a link to dash. My bad, until now I'm using NoExtract for files I don't want to have, I wasn't aware that a file or link we want to have gets lost. Okay, so I wasn't *completely* losing my mind (what little of it there is!). Here's what I think is happening (probably wrong, but this is what I've deduced from further reading and some strace fun): Since (re)installing over an existing package first removes its constituent files, NoExtract alone results in the reinstallation process removing bash (and the /usr/bin/sh link). But, since the file is specified as NoExtract, the link/file isn't recreated during package extraction (it's skipped). NoUpgrade, on the other hand, prevents the file from being removed (reinstallation must therefore be considered as an upgrade for this purpose) but if it's not also specified by NoExtract, it's immediately overwritten by the new copy. So, if my understanding is correct, this would explain why both options must be used in order to keep something relatively unscathed. NoUpgrade prevents its removal (or more accurately it prevents its upgrade); NoExtract prevents it from being overwritten. Disclaimer: I haven't looked at the pacman sources yet. This is exclusively from observation and what my (admittedly very limited) understanding of pacman provides. Benjamin
