systemd-cron/systemd-cron — pull request #32 by wavexx (2014-11-05 15:04:07+00:00)
Title: Only manipulate the shell command for known shells.

We cannot assume the shell language is always KSH compatible.
Perform a crude check by matching the shell binary against a known list.

This was one of my recommendations when implementing command manipulations, as I was guilty of using weird shells (including *gasp* emacs) for a long time.