Signals

Signals are a Unix invention for asynchronous signaling, and were integrated into the C standard (<signal.h>). When a process receives a signal (send by hardware, or another process using =raise()=), a signal handler is called. A signal handler is a C function that handles the signal; which function to call on which signal is defined by passing its function pointer to the =signal()= function. (If no signal handler is defined for a given signal, a =raise()= of that signal aborts the program.)

Signal handling is tricky, since it breaks the single-control-flow structure of a C program. Make sure you read the manuals...

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Category: InterProcessCommunication