On Thursday 28 March 2013 14:43:06 James Antill wrote: > I agree this is a problem, everyone who knows how Fedora packaging > works has said, to you, some variant of: > The technical problem is being able to install multiple versions of a > package, and you can do that now (and have been able to for the last 10 > years). > Here is a long list of technical reasons why your desire to have all > the parallel installable versions of "foo" called "foo" is not going to > work. > This is because you don't understand the problem, or are ignoring it. > Using the package name to differentiate N different packages is by far > the easiest thing for packagers and all of our packaging tools. It is > also almost always the best thing for the user as well, and in the cases > it isn't so great can be worked around. > No, the reason to "dismiss" the idea is because it is worse than the > alternative that works now. > Maybe if you think of the problem differently it will help you > understand. > Imagine that we have N packages that provide a "bourne shell" and they > are called bash, dash, ksh and pdsh ... they all want to be allowed to > be installed "in parallel" and updated at different times etc. and > currently we can do this, we just give them different package names. > However they are "obviously" just name mangled versions of "sh" and it > looks ugly for the user not to be able to do "yum install sh" or > "yum upgrade sh" and it do "something"[1]. So the feature is requested > that we rename all four of them to "sh" and "just" have some new rpm tag > saying "this is the bash variant" etc. > koji/bodhi/yum/rpm/etc. will all have to be updated to understand this > new rpm tag, which will be a huge amount of work, but at least the user > will be able to run "yum install sh" at the end. > So we now have bash, dash, ksh and pdsh all in a single specfile ... > hopefully a single package maintainer owns all three versions, because > if not then every change for each stream will have to be co-ordinated > with every other maintainer. All the maintainers will also now have to > download all the data for each variant (git clone sh will now require > all the data), and they'll either need to test all variants whenever > they make a change or hope they didn't break anything in any of the > other variants. > But, it turns out, those variants are not _identical_ (or we could just > have one of them, surely) so the other packagers whose packages require > or conflict with only "the pdsh variant of sh" will have to use some > much more obscure method to specify exactly which versions of "sh" they > require/conflict with (or users will be very unhappy that it should work > with the "ksh variant" installed, but the packaging doesn't allow it). > Also, it turns out, some users may actually want have installed "the > ksh variant" and not "the pdsh" variant[2] ... so now all of our UI > needs some way for the user to easily differentiate between the > different versions of "sh" (means we'll need to output that new rpm tag > in all the places we currently output nevra, and likely all the places > we output name). > Then we'll need to change the input UI side so that the user can > specify that tag everywhere (Eg. yum list <only show me the zsh > variants>). > Then we'll also have the problem of users talking to > developers/maintainers and saying things like "I have a bug in sh" or "I > install sh and XYZ doesn't seem to work", so we need to somehow fix all > the users to not just say "sh" all the time anyway. > That seems like a _lot_ of work, and a much more complicated solution > than just having all 4 packages "Provide: sh" (or even have the user use > "yum install /bin/sh") ... and ultimately provides no actual benefit. > [1] Some random version of sh, all uninstalled versions or a random > uninstalled version or something else are all viable definitions of > "something" here. > [2] For example crazy users not wanting to put things in rpms, and just > managing the deps. by hand (those variant tag things are really > confusing). My initial concern, multiversion, would have nothing to do with aliases, and just thinking on solving/implementing it would require another thread. The fact that sh would reflect bash, csh, pdsh, etc. is completely another point. By the way, i think i've seen yum install vnc-server (generic) install tigervnc-server (specific or fedora default). pkg-1.0.x.rpm pkg-2.0.x.rpm Again: pkg2-2.0.0.rpm, no sense. But you maybe are right in some point, UNIX is not really multiversion welcome, for starters, you can not have two mplayer binaries in an usual way (/usr/bin), that's obvious, and that's cause the path for binaries itself, you would need /usr/bin/mplayer-1 and /usr/bin/mplayer-2 and maybe some default/ alternatives for /usr/bin/mplayer. so the version becomes part of the command itself (mplayer-1 or mplayer-2) but that's at binary file level and cause filesystem hierarchy works that way (and I'm not saying it should keep working that way, but that's a filesystem issue not a packaging issue). -- devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxxx https://admin.fedoraproject.org/mailman/listinfo/devel
