order of files

[Edmund GRIMLEY EVANS]

This is a feature request rather than a bug report.

At present tar stores files in their directory order. Unfortunately,
the directory order is arbitrary and may depend on what file system
you are using. I think it would be better if tar stored the files in
name order. This would be helpful when tar is used in packaging
software: the MD5 sum of the package could then more easily be made
independent of the file system being used.

If you think this is a good idea, probably I could implement it myself
and send you a patch.

Note that it is rather hard to get a canonical ordering in a portable
way without modifying tar as you can't add a directory to an archive
without adding the files it contains. If this were possible, then I
could get a canonical ordering with something like:

find foo-1.2.3 | sort |
  ( while read x ; do tar --dir-only -rf foo-1.2.3.tar "$x" ; done )

(assuming no file name contains a '\n'!)

However, it might be neater if tar used a canonical ordering by
default. What do you think?

Edmund