Added entries about SANE_I18N() and documentation directories.

doc/backend-writing.txt

@@ -1,4 +1,4 @@
-2001-04-13
+2001-05-04
 
 Here are a few rules that should help writing a SANE-conformant
 backend:
@@ -120,6 +120,10 @@ backend:
   to README, AUTHORS and sane-backends.lsm. The README entry should point to
   your documentation (man-page, website, readme).
 
+* If you want to include READMEs, HTML files or other documentation,
+  please create your own directory (doc/backendname) and store your files
+  in this directory.
+
 * Don't use printf, fprintf or perror to output debug or error messages.
   Use the DBG macro instead. If your backend can't detect a scanner for
   whatever reason it shouldn't output anything as long as
@@ -127,3 +131,11 @@ backend:
 
 * Don't use exit() in your backend. You will exit the whole program, not only your
   backend.
+
+* To support translation of SANE options, please mark the descriptions (desc) and
+  title of options with SANE_I18N(). Do the same for string lists used in options.
+  The name of options mustn't be marked. This way translation of your backend's
+  options is easier. Do *not* mark macros. Especially you don't need to mark standard
+  option strings like SANE_TITLE_NUM_OPTIONS as this is already done in saneopts.h.
+
+  Example: s->opt[5].title = SANE_I18N("Enhancement");