`du` check for directory loop avoidance

[Jeff Kirkpatrick]

A Red Hat customer has registered a concern over the non-zero exit code that results when du traverses a directory loop, i.e. a chrooted environment.

The recent Red Hat Enterprise Linux 6.5 errata http://rhn.redhat.com/errata/RHSA-2013-1652.html includes a change to the warning message received (FROM "WARNING: Circular directory structure. This almost certainly means that you have a corrupted file system." TO " du: mount point `/var/named/chroot/var/named' already traversed") however there is still a non-zero exit code.

Customer states "The message may be acceptable, but it shouldn't give a failure exit value for a situation that is not an error. In reading the technical notes, I see the non-zero exit code was deliberate. But I don't understand why it would be considered an error."

When I reached out to our engineering organization I received the following response:

"Non-zero exit code was chosen by upstream - we only followed their decision. Part of the discussion is at the 
http://debbugs.gnu.org/cgi/bugreport.cgi?bug=11844 and second at http://lists.gnu.org/archive/html/bug-coreutils/2010-01/msg00011.html ... 
However, I don't see explicit reasons for the non-zero exit code. If you want to ask for the reason, you may write an email to address@hidden."

Can anyone elaborate on why the decision to use a non-zero exit code?

Best Regards,

Jeff Kirkpatrick,
Support Relationship Manager
Strategic Customer Engagement
Red Hat Global Support Services

For Immediate Technical Support - 1.888.GO.REDHAT (888.467.3342)