Signals

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. ...

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