Symbol Number Action Meaning SIGHUP 1 exit Hangs up. SIGINT 2 exit Interrupts. SIGQUIT 3 core dump Quits. SIGILL 4 core dump Illegal instruction. SIGTRAP 5 core dump Trace trap. SIGIOT 6 core dump IOT instruction. SIGEMT 7 core dump MT instruction. SIGFPE 8 core dump Floating point exception. SIGKILL 9 exit Kills (cannot be caught or ignored). SIGBUS 10 core dump Bus error. SIGSEGV 11 core dump Segmentation violation. SIGSYS 12 core dump Bad argument to system call. SIGPIPE 13 exit Writes on a pipe with no one to read it. SIGALRM 14 exit Alarm clock. SIGTERM 15 exit Software termination signal.