Siggy Brentrup <deb...@psycho.i21k.de> writes: > On Thu, Jul 23, 2009 at 11:19 -0400, Sam Hartman wrote: > > >> Folks, there was a longish discussion on IRC starting about an hour >> ago about dash and bash. > > These discussions are extremely long standing :) The move away from > bash has been aimed at long before I vanished from the project in 2004. > I'm really upset that 5 years are not enough to accomplish the move. > >> I agree we want to move the default /bin/sh to /bin/dash. >> However I'm failing to understand why we want dash to be essential. >> If I'm not using dash as my /bin/sh why do I need it? > > So you are complaining about a small package (installed size 224) > becoming essential while forcing the embedded ppl to work around a > monster (installed size 1236); numbers taken from my Ubuntu laptop > where both are essential, I hope only for a limited period of time. > Although preferring CLI over GUI I don't use both of them, I prefer > zsh for my daily work but my #!/bin/sh scripts are always posixly > correct.
No, complaining about replacing shackles with handcuffs. >> If the answer is that we really do want it everywhere independent of >> what /bin/sh is, that's fine. However, that's not obvious to me. > > As long as /bin/sh refuses extensions to posix I agree with you, but > bashism has been a cuss word for years before 2004. > >> So, a proposal for doing a switch with dash not essential. > >> 1) all /bin/sh shells know about each other. 1b) All /bin/sh shells must behave as if they where essential. They must work while being unconfigured and so on. >> 2) The prerm script for a /bin/sh shell finds another /bin/sh shell >> and updates the symlink if the current /bin/sh link is the one being >> removed. > >> 3) The postinst for a /bin/sh shell can update the link if it >> decides that the installed shell would make a better /bin/sh > >> 4) There is a package `the-shell ' that is essential and pre-depends >> on one of the /bin/sh shells. > > Maybe "posixly-correct-shell" would be a better name. > > Summing up you suggest making a virtual package - however it's called > - essential. While I think I grok your intentions, I doubt dpkg > will follow, please read carefully: > > http://www.debian.org/doc/debian-policy/ch-binary.html#s3.8 And what exactly do you mean? Nothing in there about virtual packages. >> Variations: > >> 1) You could have a registration mechanism. My assumption is the >> set is small enough static is good > >> 2) I assume that package operations cannot take place between >> calling the prerm script and actually removing the package. If that >> is false, you could make sure that you are changing the link to a >> configured shell It is false afaik. You can deconfigure any number of packages before starting to remove any of them. >> I really don't mind if we go forward with the current proposal. >> However, I think I and a lot of other people would appreciate clarity, >> so far not expressed, about why dash needs to be essential. > > See debian-policy cited above. > > looking-forward-for-posixly-correct-/bin/sh-ly yours > Siggy Say you have only shell-1 installed to provide /bin/sh. The big question is if apt/aptitude/synaptic/.../dpkg will ever deconfigure or even uninstall shell-1 before it unpacks shell-2. Can the following sequence happens? deconfigure the-shell deconfigure shell-1 remove shell-1 unpack shell-2 configure shell-2 configure the-shell If this sequence ever happens then the system is without /bin/sh for a time. Not a good idea. I think the above is unlikely but can possibly happen and nothing in Depends or Pre-Depends can prevent it. But the prerm script could (should) fail if it can not find another /bin/sh provider to at least don't make the system unusable. MfG Goswin -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org
