Signals as a Linux debugging tool

By focusing on the analysis of data captured using signal handlers, you can speed up the most time-consuming part of debugging: finding the bug. This article gives a background on Linux signals with examples specifically tested on PPC Linux, then goes on to show how to design your handlers to output information that lets you quickly home in on failed portions of code.

Signals are software interrupts that send information about an occurrence of an asynchronous event to an executing program, or process. Signals are generated for a variety of reasons such as timer expiration. Most hardware traps -- illegal instructions, access to invalid addresses, and so on -- are converted to signals.

Signals can be generated by the process itself, or they can be sent from one process to another. A variety of signals can be generated or delivered, and they have many uses for programmers.