Non sono un fan di posix ma i manuale dice questo
int kill(pid_t pid, int sig);
dove sig sta per segnale preso dalla lista sotto.
SIGHUP 1 Hangup (POSIX)
SIGINT 2 Interrupt (ANSI)
SIGQUIT 3 Quit (POSIX)
SIGILL 4 Illegal instruction (ANSI)
SIGTRAP 5 Trace trap (POSIX)
SIGABRT 6 Abort (ANSI)
SIGIOT 6 IOT trap (4.2 BSD)
SIGBUS 7 BUS error (4.2 BSD)
SIGFPE 8 Floating-point exception (ANSI)
SIGKILL 9 Kill, unblockable (POSIX)
SIGUSR1 10 User-defined signal 1 (POSIX)
SIGSEGV 11 Segmentation violation (ANSI)
SIGUSR2 12 User-defined signal 2 (POSIX)
SIGPIPE 13 Broken pipe (POSIX)
SIGALRM 14 Alarm clock (POSIX)
SIGTERM 15 Termination (ANSI)
SIGSTKFLT 16 Stack fault
SIGCLD SIGCHLD Same as SIGCHLD (System V)
SIGCHLD 17 Child status has changed (POSIX)
SIGCONT 18 Continue (POSIX)
SIGSTOP 19 Stop, unblockable (POSIX)
SIGTSTP 20 Keyboard stop (POSIX)
SIGTTIN 21 Background read from tty (POSIX)
SIGTTOU 22 Background write to tty (POSIX)
SIGURG 23 Urgent condition on socket (4.2 BSD)
SIGXCPU 24 CPU limit exceeded (4.2 BSD)
SIGXFSZ 25 File size limit exceeded (4.2 BSD)
SIGVTALRM 26 Virtual alarm clock (4.2 BSD)
SIGPROF 27 Profiling alarm clock (4.2 BSD)
SIGWINCH 28 Window size change (4.3 BSD, Sun)
SIGPOLL SIGIO Pollable event occurred (System V)
SIGIO 29 I/O now possible (4.2 BSD)
SIGPWR 30 Power failure restart (System V)
SIGUNUSED 31 ---
Altre info le trovi quà:
http://pubs.opengroup.org/onlinepubs/009604599/functions/kill.html