First try as a C program.

src/server/updateLysKOM.c

+/*
+ * $Id: updateLysKOM.c,v 1.1 1994/03/06 19:59:55 ceder Exp $
+ * Copyright (C) 1994  Lysator Academic Computer Association.
+ *
+ * This file is part of the LysKOM server.
+ * 
+ * LysKOM is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by 
+ * the Free Software Foundation; either version 1, or (at your option) 
+ * any later version.
+ * 
+ * LysKOM is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with LysKOM; see the file COPYING.  If not, write to
+ * Lysator, c/o ISY, Linkoping University, S-581 83 Linkoping, SWEDEN,
+ * or the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, 
+ * MA 02139, USA.
+ *
+ * Please mail bug reports to bug-lyskom@lysator.liu.se. 
+ */
+
+#include <stdio.h>
+#ifdef HAVE_STDLIB_H
+#  include <stdlib.h>
+#endif
+#include <signal.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <errno.h>
+#ifdef HAVE_STRING_H
+#  include <string.h>
+#else
+#  ifdef HAVE_STRINGS_H
+#    include <strings.h>
+#  endif
+#endif
+#ifndef HAVE_STRCHR
+#  define strchr index
+#endif
+#include <time.h>
+#include <unistd.h>
+
+#ifndef HAVE_DIFFTIME
+#  include "tmp-difftime.h"
+#endif
+
+void
+checkstatus(FILE *fp)
+{
+    char lbuf[80];
+    char buf2[300];
+    struct stat sbuf;
+
+    if (fstat(fileno(fp), &sbuf) < 0)
+    {
+	perror("updateLysKOM: stat failed");
+	exit(1);
+    }
+    
+    if (difftime(time(NULL), sbuf.st_mtime) < 3600)
+    {
+	/* NOP */
+    }
+    else if (difftime(time(NULL), sbuf.st_mtime) < 2*3600)
+    {
+	/* Send mail to creator of file, the first line in the file. */
+
+	if (fgets(lbuf, 80, fp) == NULL)
+	{
+	    perror("updateLysKOM: fgets failed");
+	    exit(1);
+	}
+	if (strchr(lbuf, '\n'))
+	    *strchr(lbuf, '\n') = '\0';
+	sprintf(buf2, "echo 'Reminder: LysKOM is still not running.'|Mail %s",
+		lbuf);
+	if (system(buf2) != 0)
+	{
+	    perror("updateLysKOM: system failed");
+	    exit(1);
+	}
+    }
+    else
+    {
+	if (system("echo 'Note: LysKOM is down' | Mail ceder") != 0)
+	{
+	    perror("updateLysKOM: system failed (2)");
+	    exit(1);
+	}
+    }
+}
+	
+
+int
+main (int    argc,
+      char **argv)
+{
+    int i;
+    FILE *fp;
+
+    if (getuid() == 0 || geteuid() == 0)
+    {
+	fprintf(stderr, "%s: this program should run as lyskom, not root\n",
+		argv[0]);
+	exit(1);
+    }
+
+    /* Parse command line arguments. */
+    for (i = 1; i < argc && argv[i][0] == '-'; i++)
+	switch (argv[i][1])
+	{
+	case 'V':
+	case 'v':
+	    fprintf(stderr, "updateLysKOM $Revision: 1.1 $\n");
+	    exit(0);
+
+	default:
+	    fprintf(stderr, "usage: %s [-V]\n", argv[0]);
+	}
+
+    fp = fopen(DEFAULT_PREFIX "/etc/status", "r");
+    if (fp != NULL)
+    {
+	checkstatus(fp);
+    }
+    else
+    {
+	long pid;
+	fp = fopen(DEFAULT_PREFIX "/etc/pid", "r");
+	if (fp == NULL)
+	{
+	    fprintf(stderr, "%s: %s: ", argv[0], DEFAULT_PREFIX "/etc/pid");
+	    perror("");
+	    exit(1);
+	}
+
+	pid = 0;
+	fscanf(fp, "%lu", &pid);
+	if (pid == 0 || pid == 1)
+	{
+	    fprintf(stderr, "%s: got pid %ld.\n", argv[0], pid);
+	    exit(1);
+	}
+	
+	if (kill(pid, SIGUSR1) != 0)
+	{
+	    if (errno != ESRCH)
+	    {
+		fprintf(stderr, "%s: kill(%ld, SIGUSR1) failed", argv[0], pid);
+		perror("");
+		exit(1);
+	    }
+	    close(0);
+	    close(1);
+	    close(2);
+	    if (0 != open("/dev/null", O_RDONLY)
+		|| 1 != open(DEFAULT_PREFIX "etc/stdout.log", 
+			     O_WRONLY|O_APPEND|O_CREAT, 0666)
+		|| 2 != open(DEFAULT_PREFIX "etc/stdout.log", 
+			     O_WRONLY|O_APPEND|O_CREAT, 0666))
+	    {
+		fprintf(stderr, "%s: open", argv[0]);
+		perror("");
+	    }
+	    execl(DEFAULT_PREFIX "/bin/lyskomd", "lyskomd", (char *)0);
+	    fprintf(stderr, "%s: execl() failed: ", argv[0]);
+	    perror("");
+	    exit(1);
+	}
+    }
+
+    exit(0);
+}