On Thu, Sep 24, 2020 at 08:10:04AM -0600, Charles Curley wrote: > On Thu, 24 Sep 2020 09:53:59 -0400 > Greg Wooledge <wool...@eeg.ccf.org> wrote: > > > RANDOM is a bashism, not available in sh, so that won't work in a > > crontab unless you've altered which shell cron is using to parse the > > crontab. > > Well, that's interesting. The file I pulled that from (in /etc/cron.d) > sets two variables explicitly: > > SHELL=/bin/sh > PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin > > And the machine that it runs on shows: > > root@hawk:~# ll /bin/sh > lrwxrwxrwx 1 root root 4 Jan 17 2019 /bin/sh -> dash*
In dash, RANDOM does nothing; it's just an empty variable. And as it turns out, dash treats that as a zero. unicorn:~$ dash $ echo $((1 + RANDOM % 1200)) 1 $ echo $((1 + % 1200)) dash: 2: arithmetic expression: expecting primary: "1 + % 1200" $ echo $((1 + XYZZY % 1200)) 1 So you're just doing "sleep 1" every time.
