Ulrich Marx writes:

hello

i had some trouble with the filedescriptor in udhcp.
Two things happened on my device:
1.) broken or not connected cable (no dhcp-server)
2.) daemonizing (starting with option -b)

i got a filedescriptor fd=0 from function raw_socket,
after daemonizing (daemon call) the fd is closed.
Client can't recieve data's anymore.

i fixed this problem (like pidfile handling):

networking/udhcp/socket.c

@@ -142,6 +142,8 @@ int raw_socket(int ifindex)
 		return -1;
 	}
 
+	while (fd >= 0 && fd < 3) fd = dup(fd); /* don't let daemon close fds on us */
+	
 	sock.sll_family = AF_PACKET;
 	sock.sll_protocol = htons(ETH_P_IP);
 	sock.sll_ifindex = ifindex;