I just spent the weekend (well, like an hour a day...kids, life, you know how it is) trying to track down why a bunch of new CentOS 5.2 installs at $job_2 couldn't pipe:
$ ls foo foo $ ls | grep foo $ echo $? 141
(Actually, I didn't think to look at the error code 'til someone else pointed it out…141 turns out to be SIGIPE) In the end, it would have been quicker if I'd simply searched for the first thing I saw when logging in:
-bash: [: =: unary operator expected -bash: [: -le: unary operator expected
This was particularly aggravating to track down because not every machine was doing this, and no matter what I thought to look at (/etc contents, /tmp permissions (those have a habit of going wonky on me for some reason), SELinux) I couldn't figure out what was different.
Turned out to be an upstream bug in nss_ldap. (The Bugzilla entry makes for some interesting reading, to be sure…) And I didn't see it on each machine because I hadn't upgraded after installation on all machines. (They're not yet in production, and I'm working on getting my kickstart straight.)
Man, it was gratifying to upgrade nss_ldap and see the problem go away…