1 #include <signal.h> 2 #include <errno.h> 3 killpg(pid_t pgid,int sig)4 int killpg(pid_t pgid, int sig) 5 { 6 if (pgid < 0) { 7 errno = EINVAL; 8 return -1; 9 } 10 return kill(-pgid, sig); 11 } 12