#include #include #include int system(command) char * command; { int wait_val, wait_ret, pid; __sighandler_t save_quit, save_int, save_chld; if( command == 0 ) return 1; save_quit = signal(SIGQUIT, SIG_IGN); save_int = signal(SIGINT, SIG_IGN); save_chld = signal(SIGCHLD, SIG_DFL); if( (pid=vfork()) < 0 ) { signal(SIGQUIT, save_quit); signal(SIGINT, save_int); signal(SIGCHLD, save_chld); return -1; } if( pid == 0 ) { signal(SIGQUIT, SIG_DFL); signal(SIGINT, SIG_DFL); signal(SIGCHLD, SIG_DFL); execl("/bin/sh", "sh", "-c", command, (char*)0); _exit(127); } /* Signals are not absolutly guarenteed with vfork */ signal(SIGQUIT, SIG_IGN); signal(SIGINT, SIG_IGN); printf("Waiting for child %d\n", pid); if (wait4(pid, &wait_val, 0, 0) == -1) wait_val = -1; signal(SIGQUIT, save_quit); signal(SIGINT, save_int); signal(SIGCHLD, save_chld); return wait_val; }