API message table inspection utilities

Add doxygen tags for show/clear commands

Change-Id: Ic939c561b15b0b720a8db1ecacc17e3d74419e1d
Signed-off-by: Dave Barach <dave@barachs.net>

src/vlibapi/api_common.h

@@ -255,6 +255,9 @@ typedef struct
   /* Replay in progress? */
   int replay_in_progress;
 
+  /* Dump (msg-name, crc) snapshot here at startup */
+  u8 *save_msg_table_filename;
+
   /* List of API client reaper functions */
   _vl_msg_api_function_list_elt_t *reaper_function_registrations;
 

src/vpp/conf/startup.conf

@@ -8,7 +8,20 @@ unix {
 }
 
 api-trace {
+## This stanza controls binary API tracing. Unless there is a very strong reason,
+## please leave this feature enabled.
   on
+## Additional parameters:
+##
+## To set the number of binary API trace records in the circular buffer, configure nitems
+##
+## nitems <nnn> 
+##
+## To save the api message table decode tables, configure a filename. Results in /tmp/<filename>
+## Very handy for understanding api message changes between versions, identifying missing
+## plugins, and so forth.
+##
+## save-api-table <filename>
 }
 
 api-segment {