era replied to me:
> A lock file might still be a good idea, though, to deal with the
> script output: if two messages arrive shortly after each other,
> the script processes that are started might interfere with each
> other when writing to the log file. (Or is there no danger
> because each copy only writes one line?)
To me, that sounds overcautious. This depends, of course, on what the
script produces, but in this case, if I understood Duncan correctly,
there might at most be an error message or two written to standard
error. These should perhaps include a PID or something to distinguish
two processes running at the same time, if they are likely to produce
more than perhaps an occasional one-liner.
I'm not sure either what the script is supposed to do, but it
does write some output to a file /home/dhill/mailparse.log, so
there might be the potential for a conflict. Duncan, comments?
And anyway, the integrity of the log file can't be guaranteed anyhow.
Procmail never locks the log file while writing to it.
Sorry, I wasn't clear - I didn't mean procmail's own log, but the
one created by the script; I wanted to suggest the lock to
prevent two copies of the script from running at the same time,
so that they wouldn't try to access said file simultaneously.
/HW