I have written before about the usefulness of command-line scripting in computational science.

Today, while looking for some information on various file test operators in bash (e.g. to check whether a file or directory exists), I found this amazing guide. As the author puts it,

This tutorial assumes no previous knowledge of scripting or programming, but progresses rapidly toward an intermediate/advanced level of instruction . . . all the while sneaking in little snippets of UNIX® wisdom and lore. It serves as a textbook, a manual for self-study, and a reference and source of knowledge on shell scripting techniques.

For instructional purposes, all along the examples have little comments like, “explain why this is the case…”, to test your knowledge as you go through the manual. This would make it excellent for use as textbook on basic programming ideas. It is even available in PDF format, and was updated March 18th of 2008.

I can assure you that every new member of the lab will be getting a link to this guide from me. Proper knowledge of shell scripting is an amplifier of one’s productivity. An investment of a few hours learning the basics will probably return a hundred-fold savings of time over a few months. More advanced concepts are naturally learned as more difficult scenarios are encountered. I’ll be writing soon about some of the more sophisticated issues I’ve encountered using shell scripting.