tcpdump.1 is generated from tcpdump.1.in.

[tcpdump] / sll.h

diff --git a/sll.h b/sll.h
index f6c38263c9e42b5019259effcf7327ee175cefc3..bad31e27a49fe8e8a740c1e62b62d9d255e8d49f 100644 (file)
--- a/sll.h
+++ b/sll.h
@@ -4,7 +4,7 @@
  *
  * This code is derived from the Stanford/CMU enet packet filter,
  * (net/enet.c) distributed as part of 4.3BSD, and code contributed
- * to Berkeley by Steven McCanne and Van Jacobson both of Lawrence 
+ * to Berkeley by Steven McCanne and Van Jacobson both of Lawrence
  * Berkeley Laboratory.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -35,7 +35,7 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
- * @(#) $Header: /tcpdump/master/tcpdump/sll.h,v 1.3 2000-12-22 22:45:12 guy Exp $ (LBL)
+ * @(#) $Header: /tcpdump/master/tcpdump/sll.h,v 1.7.6.1 2008-05-30 01:38:21 guy Exp $ (LBL)
  */
 
 /*
@@ -60,6 +60,20 @@
  *     specified by the previous value.
  *
  * All fields except for the link-layer address are in network byte order.
+ *
+ * DO NOT change the layout of this structure, or change any of the
+ * LINUX_SLL_ values below.  If you must change the link-layer header
+ * for a "cooked" Linux capture, introduce a new DLT_ type (ask
+ * "[email protected]" for one, so that you don't give it
+ * a value that collides with a value already being used), and use the
+ * new header in captures of that type, so that programs that can
+ * handle DLT_LINUX_SLL captures will continue to handle them correctly
+ * without any change, and so that capture files with different headers
+ * can be told apart and programs that read them can dissect the
+ * packets in them.
+ *
+ * This structure, and the #defines below, must be the same in the
+ * libpcap and tcpdump versions of "sll.h".
  */
 
 /*
@@ -70,10 +84,10 @@
 
 struct sll_header {
        u_int16_t       sll_pkttype;    /* packet type */
-       u_int16_t       sll_protocol;   /* protocol */
        u_int16_t       sll_hatype;     /* link-layer address type */
        u_int16_t       sll_halen;      /* link-layer address length */
        u_int8_t        sll_addr[SLL_ADDRLEN];  /* link-layer address */
+       u_int16_t       sll_protocol;   /* protocol */
 };
 
 /*