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Examples of killsnoop-nd.stp, the Linux SystemTap version. killsnoop-nd.stp traces signals, including those sent by the kill(1) command. For example: # ./killsnoop-nd.stp FROM COMMAND SIG TO RESULT 14163 w 0 11962 0 14163 w 0 12040 0 14163 w 0 14152 0 14152 bash 9 12345 -3 14152 bash 9 14152 0 ^C13914 killsnoop-nd.st 15 14147 0 The output begins by showing the w(1) command sending three signal 0's to different processes: signal 0, and the return value, is used as an aliveness check. Then bash sends a signal 9 (SIGKILL) to PID 12345, which doesn't exist, and returns an error (-3). This is followed by a successful signal 9. These two were issued using "kill -9". Finally, I hit Ctrl-C to end this example, and this was caught and shown after the "^C". Signal 15 (SIGTERM)? I thought Ctrl-C issued signal 2 (SIGINT)... For a quick lookup of signal numbers to names, you can use the kill(1) bash builtin with -l. Eg: bash$ kill -l 1) SIGHUP 2) SIGINT 3) SIGQUIT 4) SIGILL 5) SIGTRAP 6) SIGABRT 7) SIGBUS 8) SIGFPE 9) SIGKILL 10) SIGUSR1 11) SIGSEGV 12) SIGUSR2 13) SIGPIPE 14) SIGALRM 15) SIGTERM 16) SIGSTKFLT 17) SIGCHLD 18) SIGCONT 19) SIGSTOP 20) SIGTSTP 21) SIGTTIN 22) SIGTTOU 23) SIGURG 24) SIGXCPU 25) SIGXFSZ 26) SIGVTALRM 27) SIGPROF 28) SIGWINCH 29) SIGIO 30) SIGPWR 31) SIGSYS 34) SIGRTMIN 35) SIGRTMIN+1 36) SIGRTMIN+2 37) SIGRTMIN+3 38) SIGRTMIN+4 39) SIGRTMIN+5 40) SIGRTMIN+6 41) SIGRTMIN+7 42) SIGRTMIN+8 43) SIGRTMIN+9 44) SIGRTMIN+10 45) SIGRTMIN+11 46) SIGRTMIN+12 47) SIGRTMIN+13 48) SIGRTMIN+14 49) SIGRTMIN+15 50) SIGRTMAX-14 51) SIGRTMAX-13 52) SIGRTMAX-12 53) SIGRTMAX-11 54) SIGRTMAX-10 55) SIGRTMAX-9 56) SIGRTMAX-8 57) SIGRTMAX-7 58) SIGRTMAX-6 59) SIGRTMAX-5 60) SIGRTMAX-4 61) SIGRTMAX-3 62) SIGRTMAX-2 63) SIGRTMAX-1 64) SIGRTMAX