Subject: Re: syntax ideas solicited
To: Perry E. Metzger <>
From: Andrew Brown <>
List: tech-userlevel
Date: 12/24/2001 20:17:49
>For some time, I've gotten mad at a certain behavior of cron: when I
>sleep my laptop overnight and wake it up, it starts running all the
>cron jobs that were scheduled overnight. Of course, the first thing
>that I want when I wake up my laptop is *not* to have it start doing a
>large bunch of finds. OTOH, if I leave the machine on overnight, I
>would like the jobs run.

arg.  i hate that also.

>I got the idea that what I'd do is add a small feature to cron in
>which one specifies in a crontab "if you miss this time, DO NOT try to
>run the job later". I was thinking of putting some special character
>(like a $ or a % or something) in the first column of the job time to
>indicate this.
>Any ideas on an appropriate character, or alternate syntaxes, or ideas
>on prior art, or just plain ideas?

what about = as the first character on the line, meaning that cron
should run the job at that time, iff that is the current time.  if you
leave your laptop on overnight, the time of the job will match the
current time, and if your laptop sleeps through the night, the time
won't match the job time, so it won't get run.

otoh, daily (and weekly) could be tweaked to really only run and not
at really really off times.  maybe it'd be worth filling in some
environment from cron that say, eg, how late a job is, what time it
was supposed to go off, etc.  that way any script could just for

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