coreutils: Signal specifications
1
1 2.5 Signal specifications
1 =========================
1
1 A SIGNAL may be a signal name like ‘HUP’, or a signal number like ‘1’,
1 or an exit status of a process terminated by the signal. A signal name
1 can be given in canonical form or prefixed by ‘SIG’. The case of the
1 letters is ignored. The following signal names and numbers are
1 supported on all POSIX compliant systems:
1
1 ‘HUP’
1 1. Hangup.
1 ‘INT’
1 2. Terminal interrupt.
1 ‘QUIT’
1 3. Terminal quit.
1 ‘ABRT’
1 6. Process abort.
1 ‘KILL’
1 9. Kill (cannot be caught or ignored).
1 ‘ALRM’
1 14. Alarm Clock.
1 ‘TERM’
1 15. Termination.
1
1 Other supported signal names have system-dependent corresponding
1 numbers. All systems conforming to POSIX 1003.1-2001 also support the
1 following signals:
1
1 ‘BUS’
1 Access to an undefined portion of a memory object.
1 ‘CHLD’
1 Child process terminated, stopped, or continued.
1 ‘CONT’
1 Continue executing, if stopped.
1 ‘FPE’
1 Erroneous arithmetic operation.
1 ‘ILL’
1 Illegal Instruction.
1 ‘PIPE’
1 Write on a pipe with no one to read it.
1 ‘SEGV’
1 Invalid memory reference.
1 ‘STOP’
1 Stop executing (cannot be caught or ignored).
1 ‘TSTP’
1 Terminal stop.
1 ‘TTIN’
1 Background process attempting read.
1 ‘TTOU’
1 Background process attempting write.
1 ‘URG’
1 High bandwidth data is available at a socket.
1 ‘USR1’
1 User-defined signal 1.
1 ‘USR2’
1 User-defined signal 2.
1
1 POSIX 1003.1-2001 systems that support the XSI extension also support
1 the following signals:
1
1 ‘POLL’
1 Pollable event.
1 ‘PROF’
1 Profiling timer expired.
1 ‘SYS’
1 Bad system call.
1 ‘TRAP’
1 Trace/breakpoint trap.
1 ‘VTALRM’
1 Virtual timer expired.
1 ‘XCPU’
1 CPU time limit exceeded.
1 ‘XFSZ’
1 File size limit exceeded.
1
1 POSIX 1003.1-2001 systems that support the XRT extension also support at
1 least eight real-time signals called ‘RTMIN’, ‘RTMIN+1’, ..., ‘RTMAX-1’,
1 ‘RTMAX’.
1