--- icmpinfo.c.orig	2011-02-05 21:09:14.000000000 +0100
+++ icmpinfo.c		2011-02-05 21:11:32.000000000 +0100
@@ -62,7 +62,7 @@
  *	This program has to run SUID to ROOT to access the ICMP socket.
  */
 
-char	usage[] = "Usage:  icmpinfo [-v[v[v]]] [-s] [-n] [-p] [-l]\n   -v : more and more info\n   -s : show local interface address\n   -n : no name query (dot ip only)\n   -p : no port -> service name query\n   -l : fork + syslog output\nv1.11 - 8/1995 - dl";
+char	usage[] = "Usage:  icmpinfo [-v[v[v]]] [-s] [-n] [-p] [-l] [-k]\n   -v : more and more info\n   -s : show local interface address\n   -n : no name query (dot ip only)\n   -p : no port -> service name query\n   -l : fork + syslog output\n   -k : kill background process\nv1.11 - 8/1995 - dl";
 char	*pname;
 
 int main(argc, argv)
@@ -101,6 +101,11 @@
 			case 's':
 				showsrcip++;
 				break;
+			case 'k':
+				pid_kill();
+				exit(0);
+				/*NOTREACHED*/
+				break;
 			case 'h':
 		        default :
 				err_quit(usage);
@@ -130,6 +135,7 @@
 	  openlog("icmpinfo",0,LOG_DAEMON);
 	  syslog(LOG_NOTICE,"started, PID=%d.",getpid());
 	  setsid();
+	  pid_file();
 	  close(0);
 	  close(1);
 	  close(2);