One of my QA coworkers had The Linux Phrasebook sitting on his desk. I noticed it was by Scott Granneman, and immediately thought, “if it’s by him, it’s got to be good.” As I thumbed through the pages of the book, I was impressed at the practical coverage of command line utilities including yum and rpm, apt and deb, etc. I highly recommend this book. It’s small so it’s easy to keep on hand.
For anyone wishing to write applications that take advantage of all that Linux has to offer, I recommend The Linux Programming Interface (also available from Amazon), aka TLPI. I used to recommend Stevens’ Advanced Programming in the UNIX Environment, but now I recommend TLPI because it is more comprehensive and just as readable. It’s not a small book, so a PDF makes it easier to keep on hand. I purchased my copy through the publisher, NoStarch with the coupon code “Mamaku” that gave me 30% off and a free PDF. The order total came to $80.00, including shipping.