And its binary is banned on certain macOS installations. I have two identical mac minis with the very same OS version. On one cron runs, on the other the cron binary doesn't run (killed: 9) even if I re-sign the binary in different location with my own codesigning identity. It's that banned.
That's fascinating. I'd love to see a shasum tree of both OS installs to know if this was due to some path-dependent upgrade sequence one of the machines went through; or whether this is down to some sub-model-number hardware-component stepping issue with power efficiency or something, that only one of the machines is affected by, where the implemented launchd solution is "don't let cron run."
The one machine where cron was working, had crontabs prior to upgrade to 15.x. The other had none.
I have googled back then and discovered that yes Apple specifically want us to suffer with their braindamaged launchd instead of cron, and thus they went to extraordinary lengths to get rid of working tools.
Anyway, cron is easy to rebuild from sources, so that's what I did.
Why would Apple "ban" a binary they ship with the OS? If I just run /usr/sbin/cron on my Apple Silicon Mac, the output is "Killed: 9" but if I actually create a crontab for a user, it works.
crontab exits immediately on one of the macs. The other had crontabs prior to upgrading to 15.something.