Index: head/sys/compat/linux/linux_socket.h
===================================================================
--- head/sys/compat/linux/linux_socket.h
+++ head/sys/compat/linux/linux_socket.h
@@ -237,6 +237,7 @@
 
 #define	LINUX_TCP_NODELAY	1
 #define	LINUX_TCP_MAXSEG	2
+#define	LINUX_TCP_CORK		3
 #define	LINUX_TCP_KEEPIDLE	4
 #define	LINUX_TCP_KEEPINTVL	5
 #define	LINUX_TCP_KEEPCNT	6
Index: head/sys/compat/linux/linux_socket.c
===================================================================
--- head/sys/compat/linux/linux_socket.c
+++ head/sys/compat/linux/linux_socket.c
@@ -244,6 +244,8 @@
 		return (TCP_NODELAY);
 	case LINUX_TCP_MAXSEG:
 		return (TCP_MAXSEG);
+	case LINUX_TCP_CORK:
+		return (TCP_NOPUSH);
 	case LINUX_TCP_KEEPIDLE:
 		return (TCP_KEEPIDLE);
 	case LINUX_TCP_KEEPINTVL: