Linux Signals cheetsheet
In Linux, signals are a form of inter-process communication (IPC) used to notify a process of an event that has occurred. They are a limited form of communication because they carry only a small amount of information: the signal number. Think of signals as software interrupts. When a particular event occurs (like a user pressing Ctrl+C, a child process exiting, or a timer expiring), the operating system sends a signal to the affected process(es). The process can then be configured to react to this signal in a predefined way, such as terminating, ignoring the signal, or executing a specific signal handler function ...