For people who are interested in this stuff, I really recommend just getting a copy of Advanced Programming in the UNIX Environment and flipping through all (or

For people who are interested in this stuff, I really recommend just getting a copy of Advanced Programming in the UNIX Environment and flipping through all (or most) of it. Pretty de-mystifying (and a good argument for caring about what OS you use!). Then you can pick up some book on shells (Effective Linux at the Command Line is one I'm going through right now), and you can piece a lot of it together. There's no magic, just a combo of decent ideas working together. But no single idea is hard to implement. Maybe just hard to come up with from scratch.