LJ 73: The Linux Signals Handling Model

Table 1. Listing of Signals

Name Number Default Description Action SIGHUP 1 Exit Hangup (ref termio(7I)) SIGINT 2 Exit Interrupt (ref termio(7I)) SIGQUIT 3 Core Quit (ref termio(7I)) SIGILL 4 Core Illegal Instruction SIGTRAP 5 Core Trace or breakpoint trap SIGABRT 6 Core Abort SIGEMT 7 Core Emulation trap SIGFPE 8 Core Arithmetic exception SIGKILL 9 Exit Kill SIGBUS 10 Core Bus error--a misaligned address error SIGSEGV 11 Core Segmentation fault, an address reference boundary error SIGSYS 12 Core Bad system call SIGPIPE 13 Exit Broken pipe SIGALRM 14 Exit Alarm clock SIGTERM 15 Exit Terminated SIGUSR1 16 Exit User defined signal 1 SIGUSR2 17 Exit User defined signal 2 SIGCHLD 18 Ignore Child process status changed SIGPWR 19 Ignore Power fail or restart SIGWINCH 20 Ignore Window size change SIGURG 21 Ignore Urgent socket condition SIGPOLL 22 Exit Pollable event (ref streamio(7I)) SIGSTOP 23 Stop Stop (cannot be caught or ignored) SIGTSTP 24 Stop Stop (job control, e.g., CTRL-z)) SIGCONT 25 Ignore Continued SIGTTIN 26 Stop Stopped--tty input (ref termio(7I)) SIGTTOU 27 Stop Stopped--tty output (ref termio(7I)) SIGVTALRM 28 Exit Virtual timer expired SIGPROF 29 Exit Profiling timer expired SIGXCPU 30 Core CPU time limit exceeded (ref getrlimit(2)) SIGXFSZ 31 Core File size limit exceeded (ref getrlimit(2)) SIGWAITING 32 Ignore Concurrency signal used by threads library SIGLWP 33 Ignore Inter-LWP signal used by threads library SIGFREEZE 34 Ignore Checkpoint suspend SIGTHAW 35 Ignore Checkpoint resume SIGCANCEL 36 Ignore Cancellation signal used by threads library SIGLOST 37 Ignore Resource lost SIGRTMIN 38 Exit Highest priority real-time signal SIGRTMAX 45 Exit Lowest priority real-time signal