3 files changed, 12 insertions, 4 deletions
diff --git a/networking/udhcp/Config.src b/networking/udhcp/Config.src
index 7d04bb2..8c8c11c 100644
--- a/networking/udhcp/Config.src
+++ b/networking/udhcp/Config.src
@@ -104,6 +104,14 @@ INSERT
 comment "Common options for DHCP applets"
         depends on UDHCPD || UDHCPC || UDHCPC6 || DHCPRELAY
 
+config UDHCPC_DEFAULT_INTERFACE
+	string "Default interface name"
+	default "eth0"
+	depends on UDHCPC || UDHCPC6
+	help
+	The interface that will be used if no other interface is
+	specified on the commandline.
+
 config FEATURE_UDHCP_PORT
 	bool "Enable '-P port' option for udhcpd and udhcpc"
 	default n
diff --git a/networking/udhcp/d6_dhcpc.c b/networking/udhcp/d6_dhcpc.c
index d4d29dc..fbdaa99 100644
--- a/networking/udhcp/d6_dhcpc.c
+++ b/networking/udhcp/d6_dhcpc.c
@@ -1163,7 +1163,7 @@ static void client_background(void)
 //usage:       "[-fbnq"IF_UDHCP_VERBOSE("v")"odR] [-i IFACE] [-r IPv6] [-s PROG] [-p PIDFILE]\n"
 //usage:       "	[-x OPT:VAL]... [-O OPT]..." IF_FEATURE_UDHCP_PORT(" [-P PORT]")
 //usage:#define udhcpc6_full_usage "\n"
-//usage:     "\n	-i IFACE	Interface to use (default eth0)"
+//usage:     "\n	-i IFACE	Interface to use (default "CONFIG_UDHCPC_DEFAULT_INTERFACE")"
 //usage:     "\n	-p FILE		Create pidfile"
 //usage:     "\n	-s PROG		Run PROG at DHCP events (default "CONFIG_UDHCPC_DEFAULT_SCRIPT")"
 //usage:     "\n	-B		Request broadcast replies"
@@ -1231,7 +1231,7 @@ int udhcpc6_main(int argc UNUSED_PARAM, char **argv)
 	/* Default options */
 	IF_FEATURE_UDHCP_PORT(SERVER_PORT6 = 547;)
 	IF_FEATURE_UDHCP_PORT(CLIENT_PORT6 = 546;)
-	client_data.interface = "eth0";
+	client_data.interface = CONFIG_UDHCPC_DEFAULT_INTERFACE;
 	client_data.script = CONFIG_UDHCPC_DEFAULT_SCRIPT;
 	client_data.sockfd = -1;
 
diff --git a/networking/udhcp/dhcpc.c b/networking/udhcp/dhcpc.c
index 98720b4..922c71e 100644
--- a/networking/udhcp/dhcpc.c
+++ b/networking/udhcp/dhcpc.c
@@ -1196,7 +1196,7 @@ static void client_background(void)
 //usage:       "	[-i IFACE]"IF_FEATURE_UDHCP_PORT(" [-P PORT]")" [-s PROG] [-p PIDFILE]\n"
 //usage:       "	[-oC] [-r IP] [-V VENDOR] [-F NAME] [-x OPT:VAL]... [-O OPT]..."
 //usage:#define udhcpc_full_usage "\n"
-//usage:     "\n	-i IFACE	Interface to use (default eth0)"
+//usage:     "\n	-i IFACE	Interface to use (default "CONFIG_UDHCPC_DEFAULT_INTERFACE")"
 //usage:	IF_FEATURE_UDHCP_PORT(
 //usage:     "\n	-P PORT		Use PORT (default 68)"
 //usage:	)
@@ -1265,7 +1265,7 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
 	/* Default options */
 	IF_FEATURE_UDHCP_PORT(SERVER_PORT = 67;)
 	IF_FEATURE_UDHCP_PORT(CLIENT_PORT = 68;)
-	client_data.interface = "eth0";
+	client_data.interface = CONFIG_UDHCPC_DEFAULT_INTERFACE;
 	client_data.script = CONFIG_UDHCPC_DEFAULT_SCRIPT;
 	client_data.sockfd = -1;
 	str_V = "udhcp "BB_VER;