Compiler masochism compliance.

[exim.git] / src / src / lookups / README

diff --git a/src/src/lookups/README b/src/src/lookups/README
index 7a16b83a286239dcacc92946c1906575a72a78c3..7490f0a27a8ba263a316bd9244611503bc83d267 100644 (file)
--- a/src/src/lookups/README
+++ b/src/src/lookups/README
@@ -1,11 +1,14 @@
-$Cambridge: exim/src/src/lookups/README,v 1.1 2004/10/07 13:10:01 ph10 Exp $
+$Cambridge: exim/src/src/lookups/README,v 1.2 2005/08/01 13:20:28 ph10 Exp $

 
 LOOKUPS
 -------
 
 Each lookup type is implemented by 6 functions, xxx_open(), xxx_check(),
 xxx_find(), xxx_close(), xxx_tidy(), and xxx_quote(), where xxx is the name of
 
 LOOKUPS
 -------
 
 Each lookup type is implemented by 6 functions, xxx_open(), xxx_check(),
 xxx_find(), xxx_close(), xxx_tidy(), and xxx_quote(), where xxx is the name of

-the lookup type (e.g. lsearch, dbm, or whatever).
+the lookup type (e.g. lsearch, dbm, or whatever). In addition, there is
+a version reporting function used to trace compile-vs-runtime conflicts and
+to help administrators ensure that the modules from the correct build are
+in use by the main binary.

 
 The xxx_check(), xxx_close(), xxx_tidy(), and xxx_quote() functions need not
 exist. There is a table in drtables.c which links the lookup names to the
 
 The xxx_check(), xxx_close(), xxx_tidy(), and xxx_quote() functions need not
 exist. There is a table in drtables.c which links the lookup names to the


@@ -26,11 +29,16 @@ key" style, where the key is associated with a "file name".
 For single key lookups, this means that the file name must be an absolute path.
 It is set for lsearch and dbm, but not for NIS, for example.
 
 For single key lookups, this means that the file name must be an absolute path.
 It is set for lsearch and dbm, but not for NIS, for example.
 

-When a single-key lookup file is opened, the handle returned by the xxx_open()
-function is saved, along with the file name and lookup type, in a tree. The
-xxx_close() function is not called when the first lookup is completed. If there
-are subsequent lookups of the same type that quote the same file name,
-xxx_open() isn't called; instead the cached handle is re-used.
+  lookup_absfilequery
+
+This is a query-style lookup that must start with an absolute file name. For
+example, the sqlite lookup is of this type.
+
+When a single-key or absfilequery lookup file is opened, the handle returned by
+the xxx_open() function is saved, along with the file name and lookup type, in
+a tree. The xxx_close() function is not called when the first lookup is
+completed. If there are subsequent lookups of the same type that quote the same
+file name, xxx_open() isn't called; instead the cached handle is re-used.

 
 Exim calls the function search_tidyup() at strategic points in its processing
 (e.g. after all routing and directing has been done) and this function walks
 
 Exim calls the function search_tidyup() at strategic points in its processing
 (e.g. after all routing and directing has been done) and this function walks


@@ -153,4 +161,14 @@ needed, it can return its single argument, which is a uschar *. This function
 does NOT use the POOL_SEARCH store, because it's usually never called from any
 lookup code.
 
 does NOT use the POOL_SEARCH store, because it's usually never called from any
 lookup code.
 

+xxx_report_version()
+--------------------
+
+This is called to report diagnostic information to a file stream.
+Typically it would report both compile-time and run-time version information.
+The arguments are:
+
+  FILE *stream    where to fprintf() the data to
+
+

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