ANSI Standard Signals

SIGHUP 1 hangup, generated when terminal disconnects
SIGINT 2 interrupt, generated from terminal special char
SIGQUIT 3 (*) quit, generated from terminal special char
SIGILL 4 (*) illegal instruction (not reset when caught)
SIGTRAP 5 (*) trace trap (not reset when caught)
SIGABRT 6 (*) abort process
SIGEMT 7 EMT intruction
SIGFPE 8 (*) floating point exception
SIGKILL 9 kill (cannot be caught or ignored)
SIGBUS 10 (*) bus error (specification exception)
SIGSEGV 11 (*) segmentation violation
SIGSYS 12 (*) bad argument to system call
SIGPIPE 13 write on a pipe with no one to read it
SIGALRM 14 alarm clock timeout
SIGTERM 15 software termination signal
SIGURG 16 (+) urgent contition on I/O channel
SIGSTOP 17 (@) stop (cannot be caught or ignored)
SIGTSTP 18 (@) interactive stop
SIGCONT 19 (!) continue (cannot be caught or ignored)
SIGCHLD 20 (+) sent to parent on child stop or exit
SIGTTIN 21 (@) background read attempted from control terminal
SIGTTOU 22 (@) background write attempted to control terminal
SIGIO 23 (+) I/O possible, or completed
SIGXCPU 24 cpu time limit exceeded (see setrlimit())
SIGXFSZ 25 file size limit exceeded (see setrlimit())
SIGMSG 27 input data is in the ring buffer
SIGWINCH 28 (+) window size changed
SIGPWR 29 (+) power-fail restart
SIGUSR1 30 user defined signal 1
SIGUSR2 31 user defined signal 2
SIGPROF 32 profiling time alarm (see setitimer)
SIGDANGER 33 system crash imminent; free up some page space
SIGVTALRM 34 virtual time alarm (see setitimer)
SIGMIGRATE 35 migrate process
SIGPRE 36 programming exception
SIGVIRT 37 AIX virtual time alarm
SIGALRM1 38 m:n condition variables - RESERVED - DON'T USE
SIGWAITING 39 m:n scheduling - RESERVED - DON'T USE
SIGKAP 60 keep alive poll from native keyboard
SIGGRANT SIGKAP monitor mode granted
SIGRETRACT 61 monitor mode should be relinguished
SIGSOUND 62 sound control has completed
SIGSAK 63 secure attention key

Additional signal names supplied for compatibility, only
SIGIOINT SIGURG printer to backend error signal
SIGAIO SIGIO base lan i/o
SIGPTY SIGIO pty i/o
SIGIOT SIGABRT abort (terminate) process
SIGCLD SIGCHLD old death of child signal
SIGLOST SIGIOT old BSD signal ??
SIGMAX 63 maximum signal number, 0 is not used

valid signal values: all undefined values are reserved for future use note: POSIX requires a value of 0 to be used as the null signal in kill()