Arch should support multiple versions installed at a time

correct · 2004-08-03 11:49:19

I want to use gcc 3.2, but I am not sure what would happen if I put a arch 0.4 version of the package over my old installation. It might kill my system. Bottom line is that I want to be able to have installed multiple versions of software at the same time (just like Debian does). Is there any hope Arch will be more like a developers distro?
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Dusty · 2004-08-03 15:29:38

correct wrote:

I want to use gcc 3.2, but I am not sure what would happen if I put a arch 0.4 version of the package over my old installation. It might kill my system. Bottom line is that I want to be able to have installed multiple versions of software at the same time (just like Debian does). Is there any hope Arch will be more like a developers distro?
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No. Well, not until we have about 500 times as many developers who can maintain several branches.

You can personally have multiple versions of gcc installed by building your own package. Grab the PKGBUILD for gcc 3.2 from CVS, change the name (so it doesn't overwrite the new gcc; 'oldgcc' for example), change the paths (or maybe the names of the binaries) so it doesn't clobber the new gcc files. It's a big undertaking, but it can be done; it's not any different from creating a package for a brand new program.

You could also install it to /opt or /usr/local or something (using a PKGBUILD) to ensure it doesn't overwrite the other files.

It's easy enough to test if it overwrites gcc 3.4; when you run pacman -A oldgcc-3.2-1.pkg.tar.gz, it will tell you if there are file conflicts. Don't force it, resolve the conflicts manually inside the PKGBUILD.

Dusty

rensel · 2004-08-03 15:32:17

Another question: is it possible to use different versions of a library in the same time without conflicts, like in Gentoo?

dp · 2004-08-03 15:38:16

rensel wrote:

Another question: is it possible to use different versions of a library in the same time without conflicts, like in Gentoo?

theoretically, yes, but you must watch out for conflicts while building and you spend hdd-space without reason

an app, that depend on older libs will either addapt to the new one or die out - that's evolution!

sarah31 · 2004-08-03 22:43:58

rensel wrote:

Another question: is it possible to use different versions of a library in the same time without conflicts, like in Gentoo?

yes but it really depends on the difference between the versions. you can usually run a v1 and a v2 sisde by side without a problem but running a newer version of v2 with a older release of v2 is usually not possible without some patching. perl libs can be a pain (such as sdl-perl v1 and v2).

correct · 2004-08-04 00:00:08

What I meant was that old versions of packages stay available, only they are installed in /opt/packagename or something like that when you want to install it.

So a typical use would be:
In Arch 0.4 there exists gcc 3.2.

I install gcc 3.2 in Arch 0.4. Everything is placed in standard directories.
Then, I want to install gcc 3.4.1. The gcc 3.2 files will be overwritten (or the previous installation will be undone).

Then I find some old software that needs gcc 3.2, but it's not on my system anymore. I go to archlinux type in gcc 3.2.

I do pacman -S gcc-3.2
and it's installed in /opt/packagename (or some other dir)

I now have gcc 3.2

So the critical step is to update the PKGBUILD (this can be done automatically) of an old version after a new version is available.

tehdely · 2004-08-05 02:49:36

With overlays you could easily achieve this. Problem is, nobody's managed to implement them in Linux yet. :cry:

Xentac · 2004-08-05 03:03:20

Tell me more about these mythical overlays... maybe a URL or something.

bogomipz · 2004-08-05 07:31:07

correct wrote:

I do pacman -S gcc-3.2
and it's installed in /opt/packagename (or some other dir)
I now have gcc 3.2

This is fully possible. It's just a matter of creating the /opt installed packages. There's a gcc-3.3.3 package in incoming, and I know there's also a 3.2 version around (why can't I ever learn to write down URLs that seem interesting). You could try to simply substitute all instances of 3.3.3 with 3.2.3 in the pkgbuild from incoming, or even replace them with $pkgver like it should've been. (btw, gcc-3.3 would be a better name than gcc-3.3.3 IMO)

dpb · 2004-08-05 09:54:10

bogomipz wrote:

This is fully possible. It's just a matter of creating the /opt installed packages. There's a gcc-3.3.3 package in incoming, and I know there's also a 3.2 version around (why can't I ever learn to write down URLs that seem interesting). You could try to simply substitute all instances of 3.3.3 with 3.2.3 in the pkgbuild from incoming, or even replace them with $pkgver like it should've been. (btw, gcc-3.3 would be a better name than gcc-3.3.3 IMO)

http://dpb.backarrow.org/arch/
There's PKGBUILD's for gcc 2.95.3, 3.2.3 and 3.3.3 (release 2 of 3.3.3, better than the one in incoming/forum... hmm... should perhaps change them..). They're installed in /opt and can be used by specifying the CC variable to /opt/gcc-x.x.x/bin/gcc.
They can be changed to different versions by changing the $pkgname and $pkgversion (well, 2.95.3 and 3.x PKGBUILD's are a bit different).

Arch Linux

#1 2004-08-03 11:49:19

Arch should support multiple versions installed at a time

#2 2004-08-03 15:29:38

Re: Arch should support multiple versions installed at a time

#3 2004-08-03 15:32:17

Re: Arch should support multiple versions installed at a time

#4 2004-08-03 15:38:16

Re: Arch should support multiple versions installed at a time

#5 2004-08-03 22:43:58

Re: Arch should support multiple versions installed at a time

#6 2004-08-04 00:00:08

Re: Arch should support multiple versions installed at a time

#7 2004-08-05 02:49:36

Re: Arch should support multiple versions installed at a time

#8 2004-08-05 03:03:20

Re: Arch should support multiple versions installed at a time

#9 2004-08-05 07:31:07

Re: Arch should support multiple versions installed at a time

#10 2004-08-05 09:54:10

Re: Arch should support multiple versions installed at a time

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