In POSIX systems, SIGXCPU is a signal sent to a computer program that exceeds the processor time limit.
| Description: | Exceeding CPU Time Limit (4.2 BSD ) |
|---|---|
| Default: | process completion |
| SA_SIGINFO codes | |
| (does not have specific codes) | |
SIGXCPU is the integer constant defined in the signal.h header file. The symbolic names of the signals are used instead of numbers, since in different implementations the signal numbers may vary.
Etymology
SIG - general signal prefix (from English signal ), X - shortened spelling of English. e x ceeded - exceeded, CPU - shortened English. CPU time - CPU time .
Usage
SIGXCPU is sent when the time spent by the processor to execute the process exceeds the permissible value (determined by the fcntl system call and shell).
The processor time is not the time elapsed since the process started, but only the time during which the processor was engaged in its execution (the rest of the time, the process expects I / O and the system is servicing other processes).
On some operating systems, the Boehm garbage collector uses SIGXCPU and SIGPWR to synchronize cross-process garbage collection.