[wruza]

Most: grep, find, cat, sort, tail, wc, ls, sudo, pgrep.

Interesting: comm: https://linux.die.net/man/1/comm

Compare sorted files FILE1 and FILE2 line by line.

With no options, produce three-column output. Column one contains lines unique to FILE1, column two contains lines unique to FILE2, and column three contains lines common to both files.

-1 suppress column 1 (lines unique to FILE1)

-2 suppress column 2 (lines unique to FILE2)

-3 suppress column 3 (lines that appear in both files)

Weak: adduser/useradd (hard to non-interactive), chmod (could use file/dir filter with -R).

Least: systemctl, journalctl.

[commandersaki]

One trick I learned from a UNIX greybeard in my junior days before pgrep was widely avaialble is: ps auxw | grep [p]rocessname and it will eschew the grep process in the list.