[decklin]

It's ironic that the standard one-liner for this uses a pipeline but only counts the first word of the first command of the pipeline. Given itself as input, "sort" ought to be the most used command, but "history" is the only one counted. (I bring this up not for the sake of standard HN nitpicking but to point out that you probably do want to cover at least `sort` in your workshop, and it will be underrepresented in these results, along with `grep`, `wc`, etc.)

Unfortunately, shell grammar is complex enough that a correct one-liner is probably infeasible. For example, one of my top "commands" if you count by words is an environment variable setting prepended to an actual command.

EDIT: you can get good enough results by just splitting on "|", as others have suggested here -- any parts of regular expressions, etc that aren't really commands will probably be infrequent enough to get lost in the noise, and treating || as containing an empty command won't hurt. If you're going to catch ||, though, might as well get && too... and now you're going down the rabbit hole :-)

[hackerpants]

Yup, this oversight is officially embarrassing.