SIGVTALRM
A signal is a limited form of inter-process communication used in Unix, Unix-like, and other POSIX-compliant operating systems.
Signals have been around since the 1970s Bell Labs Unix and have been more recently specified in the POSIX standard.
A Signal is a asynchronous notification sent to a process or to a specific thread within the same process in order to notify it of an event that occurred.
- When a signal is sent, the operating system interrupts the target process's normal flow of execution to deliver the signal.
- Execution can be interrupted during any non-atomic instruction.
- If the process has previously registered a signal handler, that routine is executed.
- Otherwise the default signal handler is executed.
Embedded programs may find signals useful for interprocess communications, as the computational and memory footprint for signals is small.
Read more about SIGVTALRM: Sending Signals, Handling Signals, Relationship With Hardware Exceptions, POSIX Signals, Miscellaneous Signals, See Also