--- pid.c.orig	1970-01-01 01:00:00.000000000 +0100
+++ pid.c	2011-02-05 21:10:53.000000000 +0100
@@ -0,0 +1,52 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <signal.h>
+#include <unistd.h>
+
+#define PIDFILE                 "/var/run/icmpinfo.pid"
+
+extern char *pname;
+
+void sig_handler(int);
+
+void pid_file(void)
+{
+    FILE *fp;
+
+    if ((fp = fopen(PIDFILE, "w")) != (FILE *)NULL) {
+        fprintf(fp, "%d\n", getpid());
+        fclose(fp);
+    }
+    else
+    {
+        fprintf(stderr, "\n%s: Could not write PID file `%s', terminating.\n",
+            pname, PIDFILE);
+        exit(1);
+    }
+    signal(SIGHUP, sig_handler);
+    signal(SIGINT, sig_handler);
+    signal(SIGTERM, sig_handler);
+}
+
+void sig_handler(int sig)
+{
+    unlink(PIDFILE);
+    exit(0);
+}
+
+void pid_kill(void)
+{
+    FILE *fp;
+    int pid;
+
+    if ((fp = fopen(PIDFILE, "r")) != (FILE *)NULL)
+    {
+        if (fscanf(fp, "%d", &pid) == 1)
+        {
+            kill(pid, SIGHUP);
+            sleep(1);
+        }
+        fclose(fp);
+    }
+}
+