In the early days of computing, signals were a means to deal with unusual events, and usually, their job was to reset a condition to a default state. Nowadays, with facilities such as job control, signals are used to actually instruct processes on what to do and are now more an interprocess facilities than a reset mechanism, as they were originally conceived. Each signal is associated to an action that must be performed by the process receiving it, so here is a brief list with some of the more interesting signals that the kernel can send to a process:
- SIGCHLD: This signal is sent to a parent process when a child terminates or stops.
- SIGCONT: This tells the process that has been put on hold by SIGSTOP or SGSTP to resume its execution. These three signals are used in job controlling.
- SIGHUP: This signal is sent to a process when its terminal is closed and kills it. It owes...