Survive non-existing pid file.

src/server/updateLysKOM.c

 /*
- * $Id: updateLysKOM.c,v 1.3 1994/04/04 18:58:26 ceder Exp $
+ * $Id: updateLysKOM.c,v 1.4 1994/04/05 20:30:00 ceder Exp $
  * Copyright (C) 1994  Lysator Academic Computer Association.
  *
  * This file is part of the LysKOM server.
@@ -61,28 +61,32 @@ checkstatus(FILE *fp,
 	perror("updateLysKOM: stat failed");
 	exit(1);
     }
-    
-    if (kill(pid, SIGHUP) != 0)
+
+    if (pid != 0)
     {
-	if (errno != ESRCH)
+	if (kill(pid, SIGHUP) != 0)
 	{
-	    fprintf(stderr, "%s: kill(%ld, SIGHUP) failed", progname, pid);
-	    perror("");
-	    exit(1);
+	    if (errno != ESRCH)
+	    {
+		fprintf(stderr, "%s: kill(%ld, SIGHUP) failed", progname, pid);
+		perror("");
+		exit(1);
+	    }
 	}
-    }
-    else
-    {
-	/* The signal got through... */
-	if (ldifftime(time(NULL), sbuf.st_mtime) > 1260) /* cron 10 minutes */
+	else
 	{
-	    /* ...more than once.  Strange. */
-	    fprintf(stderr, "%s: Told lyskomd to shut down.  Twice.", 
-		    progname);
-	    exit(1);
+	    /* The signal got through... */
+	    /* cron 10 minutes */
+	    if (ldifftime(time(NULL), sbuf.st_mtime) > 1260)
+	    {
+		/* ...more than once.  Strange. */
+		fprintf(stderr, "%s: Told lyskomd to shut down.  Twice.", 
+			progname);
+		exit(1);
+	    }
 	}
     }
-    
+
     if (ldifftime(time(NULL), sbuf.st_mtime) < 3600)
     {
 	/* NOP */
@@ -93,8 +97,9 @@ checkstatus(FILE *fp,
 
 	if (fgets(lbuf, 80, fp) == NULL)
 	{
-	    perror("updateLysKOM: fgets failed");
-	    exit(1);
+	    fprintf(stderr, 
+		    "updateLysKOM: LysKOM has been down for a short while\n");
+	    exit(2);
 	}
 	if (strchr(lbuf, '\n'))
 	    *strchr(lbuf, '\n') = '\0';
@@ -136,7 +141,7 @@ main (int    argc,
 	{
 	case 'V':
 	case 'v':
-	    fprintf(stderr, "updateLysKOM %d $Revision: 1.3 $\n",
+	    fprintf(stderr, "updateLysKOM %d $Revision: 1.4 $\n",
 #include "version.incl"
 		    );
 	    exit(0);
@@ -148,17 +153,20 @@ main (int    argc,
     fp = fopen(DEFAULT_PREFIX "/etc/pid", "r");
     if (fp == NULL)
     {
-	fprintf(stderr, "%s: %s: ", argv[0], DEFAULT_PREFIX "/etc/pid");
+	fprintf(stderr, "%s: warning: %s: ", argv[0], 
+		DEFAULT_PREFIX "/etc/pid");
 	perror("");
-	exit(1);
+	pid = 0;
     }
-
-    pid = 0;
-    fscanf(fp, "%lu", &pid);
-    if (pid < 2)
+    else
     {
-	fprintf(stderr, "%s: got pid %ld.\n", argv[0], pid);
-	exit(1);
+	pid = 0;
+	fscanf(fp, "%lu", &pid);
+	if (pid < 2)
+	{
+	    fprintf(stderr, "%s: got pid %ld.\n", argv[0], pid);
+	    exit(1);
+	}
     }
 	
     fp = fopen(DEFAULT_PREFIX "/etc/status", "r");
@@ -168,7 +176,8 @@ main (int    argc,
     }
     else
     {
-	if (kill(pid, SIGUSR1) != 0)
+	errno = ESRCH;		/* Set sane default if pid==0. */
+	if (pid == 0 || kill(pid, SIGUSR1) != 0)
 	{
 	    if (errno != ESRCH)
 	    {