Signals are software interrupts which sent to a program to indicate that an important event has occurred. A Signal may be handled by following one of two possible handlers:
A Default signal handler is associated with every signal that the kernel runs when handling that signal. The action that a script or program performs when it receives a signal is called the default actions. A default signal handler handles these types of different default actions.
Some of the possible default actions are −
Terminate the process.
Ignore the signal.
Dump core. It creates a file called core containing the memory image of the process when it received the signal.
Stop the process.
Continue a stopped process.