/* * system - run a shell command (Plan 9 version) */ #include <u.h>#include <libc.h> intsystem(char *s){	long pid = fork();	Waitmsg *wm; 	if (pid == 0) {		execl("/bin/rc", "rc", "-c", s, nil);		_exits("no /bin/rc");	}	if (pid < 0)		return -1;	// "can't fork";	while ((wm = wait()) != nil && wm->pid != pid)		continue;	return wm == nil? -1: wm->msg != 0 && wm->msg[0]? 1: 0;}