[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

Many executables across Debian's archives share basenames

Hi guys,

I wrote a short script that calls "apt-file find 'bin/'", filters
results to include only stuff from /bin:/sbin:/usr/bin:/usr/sbin, and
looks for basename clashes. Turns out, in Stretch, there are 97 hits.
(If you also include /usr/games, 126.)

(Of couse, I'm counting all packages, regardless of whether they specify
"Conflicts:" or not, and regardless of whether the full name is shared,
or just the basename.)

For example, packages "389-ds-base" and "dmucs", both provie a command
called "monitor". The former's command is located in /usr/sbin, the
latter's in /usr/bin. Neither package conflicts with the other.

I think this has at least two implications:

1. Which exact executable gets called using a given command, depends
   entirely on $PATH, which, let's face it, is sometimes a mess (as
   scripts, .profile's, .bashrc's, third-party installers, automagic
   pasta, etc like to redefine and manipulate it).

Some of these commands are obviously compatible (or at least are
well-known, and have a lowest common denominator) and work fine as
drop-in replacements, like newaliases or mailq.

Some however, have different behavior (like rm from coreutils vs from
safe-rm), or are actually completely unrelated (like ztest from
zfsutils-linux and from zutils).

Scripts that rely on the existence of a command, will usually just look
for it in $PATH and assume it's the one they're expecting - I doubt many
people care to parse "foo --version" for all 17 possible implementations
of foo (including GNU Coreutils, all the BSDs, etc). I've seen this in
the wild a lot, I'm guilty of this myself, and I honestly wouldn't
expect "arcstat" to do two completely different things on a system with
ZFS, and on a system with Nordugrid (and what happens when both are
installed is entirely up to $PATH...).

2. (I know this is crazy, unsupported, violates FHS, kills kittens, and
   I'm actually Asking For Trouble by doing this, but whatever.) I can't
   safely symlink /sbin to /bin, and I can't do a /usr -> / either.

Which kinda sucks, as some Other Distros have done it and are happily
rolling with it. I know some programs will attempt weird things, or
outright freak out if this happens (I know VirtualBox used to freak out
when /usr was a symlink at all), but at least theoretically (or at least
as long as no other filename clashes happen), this should be totally
possible and kinda safe.

So, is this a bug? Is this of concern? Am I making sense?
Should I file bugs against packages that don't supply "Conflicts:"?
Should we embark on a renaming crusade? Or just leave it be?

In any case, if anyone is interested in further research, this is the
script and results for Stretch:

Please CC me in replies, I'm not a subscriber.


Reply to: