--- lp_server.c.orig	2001-09-18 03:51:31 +0400
+++ src/lp_server.c	2006-02-03 22:02:21 +0300
@@ -4,8 +4,9 @@
     Export a printer by simulating an HP JetDirect interface.
     -n connection port (default 9100)
     -w open output device write only (default r/w)
-    -d device (default /dev/lp)
+    -d device (default /dev/lp0)
     -t stty_cmds - stty commands to apply if device is serial port
+	-b - run in background mode
 
     The lp_server will bind to the connection port, and wait for
     an incoming connection.  After accepting a  connection, it 
@@ -30,10 +31,11 @@
 #include <version.h>
 
 
-char *device = "/dev/lp";
+char *device = "/dev/lp0";
 char *stty_opts;
 char *port = "9100";
 int write_only;
+int background;
 void usage(void);
 int sock, conn, dev = -1;
 int pid;
@@ -55,7 +57,7 @@
 	fd_set readfds;
 
 	name = argv[0];
-	while( ((c = getopt(argc, argv, "D:n:wd:t:r:")) != EOF) ){
+	while( ((c = getopt(argc, argv, "D:n:wd:t:r:b")) != EOF) ){
 		switch(c){
 		case 'D': debug = atoi(optarg); break;
 		case 'n': port = optarg; break;
@@ -63,11 +65,27 @@
 		case 'r': restrict = optarg; break;
 		case 'd': device = optarg; break;
 		case 't': stty_opts = optarg; break;
+		case 'b': background = 1; break;
 		default: usage();
 		}
 	}
 	if( optind != argc ) usage();
 
+	/* fork to background, write pid file, fall to lp user (uid 4) */
+	if( background ) {
+		FILE  *f;
+		daemon( 0, 0 );
+		f = fopen("/var/run/lp_server.pid", "w");
+		if (f) {
+			fprintf(f, "%d\n", getpid());
+			fclose(f);
+		} else
+			if( debug ) log(1,"can't create pid file");
+		 /* fall to lp user  */
+		if ( setuid(4) )
+			exit(1);
+	}
+	
 	/* step 1 - bind to the port */
 	sock = tcp_open( port );
 	if( sock < 0 ) exit(1);
@@ -231,12 +249,13 @@
 }
 
 char *msg[] = {
-"lp_server [-n port] [-w] [-d device] [-t stty_cmds]",
+"lp_server [-n port] [-w] [-d device] [-t stty_cmds] [-b]",
 "   Version " VERSION ,
 "    Export a printer by simulating an HP JetDirect interface.",
 "    -n connection port (default 9100)",
 "    -w open output device write only (default r/w)",
-"    -d device (default /dev/lp)",
+"    -d device (default /dev/lp0)",
+"    -b run in background mode",
 "    -t stty_cmds - stty commands to apply if device is serial port",
 "    -r remote_list - remote hosts allowed, in IP/netmask or hostname",
 "           separated by commas. i.e. - 130.191.20.10/24,dickory would",