Bugs item #1545658, was opened at 2006-08-24 04:27 Message generated for change (Comment added) made by loewis You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=105470&aid=1545658&group_id=5470
Please note that this message will contain a full copy of the comment thread, including the initial issue submission, for this request, not just the latest update. Category: Distutils Group: None Status: Closed Resolution: Invalid Priority: 5 Submitted By: John Levon (movement) Assigned to: Nobody/Anonymous (nobody) Summary: distutils home scheme lacks python versioning Initial Comment: The "home scheme", as described here: http://docs.python.org/inst/alt-install-windows.html seems to be broken: no version suffix is appended, yet .pyc files are not guaranteed across Python revisions. Thus, breakage can occur. This is quite annoying, as an OS vendor often would like to install stuff into /usr/lib/python2.x/ (not using vendor-packages). ---------------------------------------------------------------------- >Comment By: Martin v. Löwis (loewis) Date: 2006-09-10 23:08 Message: Logged In: YES user_id=21627 I read the example you gave. In case of a shared directory, you shouldn't use the "home" scheme. If you do anyway, you have to live with the consequences. The home scheme is called "home scheme" for a reason: the target directory is expected to be inside the user's home directory. ---------------------------------------------------------------------- Comment By: John Levon (movement) Date: 2006-09-10 22:12 Message: Logged In: YES user_id=53034 > not have the right to install Did you actually read the example I gave? Just because it's a "possible slowdown" doesn't mean that this behaviour is both inconsistent and potentially troublesome. But I suppose you don't care. ---------------------------------------------------------------------- Comment By: Martin v. Löwis (loewis) Date: 2006-09-10 21:00 Message: Logged In: YES user_id=21627 Why would a user not have the right to install to its own home directory? That's what the home scheme is there for. In any case, it seems that there won't be actual breakage, only a possible slowdown. I very much doubt that the slowdown would ever be significant, though. It seems you want to use the home scheme for something that it was not designed for. Notice that it is merely an abbreviation - you can specify the directories directly if you want to. I'm closing this as invalid: the original report ("Thus, breakage can occur.") is apparently wrong. ---------------------------------------------------------------------- Comment By: John Levon (movement) Date: 2006-09-10 20:51 Message: Logged In: YES user_id=53034 Consider a shared tree where users do not have access to write new .pyc's. Just like the standard python libraries, there could be a significant speed slowdown due to not being able to use the old .pyc's. It's the exact same case that prompts distro's to install into /usr/lib/pythonX.X/ ---------------------------------------------------------------------- Comment By: Martin v. Löwis (loewis) Date: 2006-09-10 17:26 Message: Logged In: YES user_id=21627 It's true that the format of marshal may change. More regularly, the format of .pyc files may change due to changes in the byte codes. Yet, I fail to see why this can cause breakage. The pyc format is deliberately so designed that nothing will break even if the format changes. I'm still waiting for a demonstrable problem. ---------------------------------------------------------------------- Comment By: John Levon (movement) Date: 2006-09-10 16:55 Message: Logged In: YES user_id=53034 http://www.python.org/doc/1.5.2p2/lib/module-marshal.html specifically: "Details of the format are undocumented on purpose; it may change between Python versions (although it rarely does)." Thus, anyone using the home scheme can hit these changes as the format is not architecturally guaranteed. ---------------------------------------------------------------------- Comment By: Martin v. Löwis (loewis) Date: 2006-09-10 02:13 Message: Logged In: YES user_id=21627 I fail to see the problem. Can you please provide a scenario where breakage does occur (instead of merely suggesting that it "can occur")? What is the specific error message that you get? Also, what does that have to do with OS vendors? They shouldn't use the home scheme. ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=105470&aid=1545658&group_id=5470 _______________________________________________ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
