Modified set_rand_dhcp_xid() to generate random DHCP xid if the dhtest is called multiple times within a second

dhtest.c

@@ -7,6 +7,7 @@
 #include<stdio.h>
 #include<string.h>
 #include<sys/types.h>
+#include<unistd.h>
 #include<sys/socket.h>
 #include<net/if.h>
 #include<linux/if_packet.h>

functions.c

@@ -328,7 +328,7 @@ int reset_dhopt_size()
 int set_rand_dhcp_xid()
 {
     if(dhcp_xid == 0) {
-	srand(time(NULL));
+	srand(time(NULL) ^ (getpid() << 16));
 	dhcp_xid = rand() % 0xffffffff;
     }
     return 0;