semantic/senator auto complete

semantic/senator auto complete

[Hadron]

I realise there is a mailing list, but it is very quiet and I am hoping
someone here can help now.

I have a small sample C file "bug.c"

,----
| #include <fstab.h>
| int  main()
| {
| 	fstab fedora;
| 	fedora.
| }
`----

If I open "fstab.h" in emacs then by placing the cursor at the end of
"fedora." then I get valid completions. I have then issued the command
"semanticdb-save-all-db". In the local directory there is now a
"semantic.cache" file with the following in:

,----
| ;; Object bug/
| ;; SEMANTICDB Tags save file
| (semanticdb-project-database-file "bug/"
|   :tables (list 
|    (semanticdb-table "bug.c"
|     :major-mode 'c-mode
|     :tags '(("fstab.h" include (:system-flag t) (dependency-file "/usr/include/fstab.h") [1 19]) ("main" function (:type "int") nil [20 59]))
|     :file "bug.c"
|     :pointmax 60
|     :unmatched-syntax 'nil
|     )
|    )
|   :file "semantic.cache"
|   :semantic-tag-version "2.0"
|   :semanticdb-version "2.0"
|   )
`----

My question is : how do I get semantic to open & parse the cache file
properly in my next emacs session when I open bug.c? I have to manually
open "fstab.h" in order to get completions to work for the types it
contains. So what job is the cache doing? Is it not possible to get
completion without manually opening each and every file?