Re: htdig: Can't run htmerge from cron?

Gilles Detillieux (
Fri, 22 Jan 1999 12:19:53 -0600 (CST)

According to Edmond Abrahamian:
> On Fri, 22 Jan 1999, Ivo Jansch wrote:
> > I've put the rundig script in the root crontab file so it runs every
> > night.
> >
> > However it fails at htmerge. I ran it in verbose mode, and this was last
> > nights output:
> >
> There's an answer to this in the archives, and many proposed solutions.
> The one that was simplest for me and that works is to use csh instead of
> bash in the shell that does the job.

Using /bin/ash instead of /bin/bash is an even easier workaround than using
/bin/csh, as ash uses the same syntax (more or less) as bash uses. However,
that doesn't get to the root of the problem, which is that vixie-cron on
Red Hat 5.0 & 5.1 doesn't handle SIGCHLD correctly. This could potentially
be a problem with other cron jobs too. The best fix, IMHO, is to upgrade
vixie-cron to the one from the 5.2 distribution.

Using another shell seems to work around the problem, presumably because
these other shells reset SIGCHLD handling back to the default, which is
what cron should be doing. The bash shell doesn't seem to do this, so
you could potentially run into problems with any cron job that uses bash
(most do by default)! It just happens that htmerge is the most obvious
and consistent program to bring out this bug.

Gilles R. Detillieux              E-mail: <>
Spinal Cord Research Centre       WWW:
Dept. Physiology, U. of Manitoba  Phone:  (204)789-3766
Winnipeg, MB  R3E 3J7  (Canada)   Fax:    (204)789-3930
To unsubscribe from the htdig mailing list, send a message to containing the single word "unsubscribe" in
the body of the message.

This archive was generated by hypermail 2.0b3 on Mon Jan 25 1999 - 08:15:24 PST