I'm in a similar situation, without the system commands. We're running on Windows (not by my choice, but that's a topic for somewhere else) and the most intensive system call I do is pretty trivial.

I attempted to get people who know Perl to review my code, but it seems that I am the one with the most Perl knowledge on site right now. Or at least, no one else who knows Perl can be torn away from their tasks to review my code. My approach has been to make it as clear as possible what I am doing (especially since one of my tasks was to update a script written by someone who liked the "job security through obscurity" approach (and of course has since left)).

My code is most likely something that can be optimized to run more efficiently, and most definitely in a more Perlish mannner. But even where I do use concise code I comment the heck out of it. I have one particular script that is about 60% comments. This seems drastic, but it is very clear to people who don't know Perl what the script is doing or trying to do.

I have at least one advantage, from the sounds of it -- everyone who is reviewing my code is also a software engineer, so they are familiar with C/C++ at least, and reading Perl (well, my Perl, anyway) isn't a great stretch. If your co-workers are not programmers, then I think it might be more trouble than it is worth to try to get them up to speed on general programming practices. If/when you leave, and they need to fix the script, it might be better for them to hire on a contractor to do it for them.

My two copper-plated zinc bits.