Signals are software interrupts. There are signals for aborting a program, floating point exceptions, illegal instruction traps, user-signaled interrupts, segment violation, and program termination. Additional semantics hold for the BeOS implementation see "Be Specific Signal Handling."

• These signals, described in "signal.h Signal descriptions", are defined as macros in the signal.h file.
• "signal" specifies how a signal is handled: a signal can be ignored, handled in a default manner, or be handled by a programmer-supplied signal handling function.
• "raise" calls the signal handling function
• "Signal function handling arguments" describes the pre-defined signal handling macros that expand to functions.