Docs: notes on DBM library changeovers

diff --git a/doc/doc-docbook/spec.xfpt b/doc/doc-docbook/spec.xfpt
index 9a52502d25a63dbde91e308424835722590dc5bc..8d61543cdff8be0b6ff22e397af0aab0bac1b730 100644 (file)
--- a/doc/doc-docbook/spec.xfpt
+++ b/doc/doc-docbook/spec.xfpt
@@ -1764,6 +1764,12 @@ distributors have chosen to bundle different libraries with their packaged
 versions. However, the more recent releases seem to have standardized on the
 Berkeley DB library.
 
 versions. However, the more recent releases seem to have standardized on the
 Berkeley DB library.
 

+.new
+Ownership of the Berkeley DB library has moved to a major corporation;
+development seems to have stalled and documentation is not freely available.
+This is probably not tenable for the long term use by Exim.
+.wen
+

 Different DBM libraries have different conventions for naming the files they
 use. When a program opens a file called &_dbmfile_&, there are several
 possibilities:
 Different DBM libraries have different conventions for naming the files they
 use. When a program opens a file called &_dbmfile_&, there are several
 possibilities:


@@ -1852,6 +1858,17 @@ DBMLIB=/usr/local/lib/db-4.1/libdb.a
 There is further detailed discussion about the various DBM libraries in the
 file &_doc/dbm.discuss.txt_& in the Exim distribution.
 
 There is further detailed discussion about the various DBM libraries in the
 file &_doc/dbm.discuss.txt_& in the Exim distribution.
 

+.new
+When moving from one DBM library to another,
+for the hints databases it suffices to just remove all the files in the
+directory named &"db/"& under the spool directory.
+This is because hints are only for optimisation and will be rebuilt
+during normal operations.
+Non-hints DBM databases (used by &"dbm"& lookups in the configuration)
+will need individual rebuilds for the new DBM library.
+This is not done automatically
+.wen
+

 
 
 .section "Pre-building configuration" "SECID25"
 
 
 .section "Pre-building configuration" "SECID25"

diff --git a/doc/doc-txt/dbm.discuss.txt b/doc/doc-txt/dbm.discuss.txt
index 50f0687137bb15e187c916de0c075e4b6e8a3cee..4f3622d690b694261ea574f1d2278fb7a8fd38cf 100644 (file)
--- a/doc/doc-txt/dbm.discuss.txt
+++ b/doc/doc-txt/dbm.discuss.txt
@@ -153,6 +153,7 @@ Berkeley DB 1.8x
 1.85 was the most widespread DB 1.x release; there is also a 1.86 bug-fix
 release, but the belief is that the bugs it fixes will not affect Exim.
 However, maintenance for 1.x releases has been phased out.
 1.85 was the most widespread DB 1.x release; there is also a 1.86 bug-fix
 release, but the belief is that the bugs it fixes will not affect Exim.
 However, maintenance for 1.x releases has been phased out.

+Exim no loger supports these releases for current builds.

 
 This dbm library can be called by Exim in one of two ways: via the ndbm
 compatibility interface, or via its own native interface. There are two
 
 This dbm library can be called by Exim in one of two ways: via the ndbm
 compatibility interface, or via its own native interface. There are two


@@ -206,6 +207,8 @@ the file name handed to it.
 DB 2.x does not do any automatic locking of its own; it does have a set of
 functions for various forms of locking, but Exim does not use them.
 
 DB 2.x does not do any automatic locking of its own; it does have a set of
 functions for various forms of locking, but Exim does not use them.
 

+Exim no longer supports these releases for current builds.
+

 
 Berkeley DB 3.x
 ---------------
 
 Berkeley DB 3.x
 ---------------


@@ -227,6 +230,20 @@ Berkeley DB 4.x
 The 4.x series is a development of the 2.x and 3.x series, and the above
 comments apply.
 
 The 4.x series is a development of the 2.x and 3.x series, and the above
 comments apply.
 

+Berkeley DB 5.x
+---------------
+
+The 5.x versions seem to be current in several Linux disributions
+as of writing (2024). Exim uses them under the assumption that the
+API is the same as the version 4.1 library.
+
+Berkeley DB 6+
+---------------
+
+These versions exist, but documentation does not seem to be available.
+Exim does not support them.
+
+

 
 tdb
 ---
 
 tdb
 ---


@@ -319,3 +336,5 @@ exists, just in case. Proceed as follows:
 
 Philip Hazel
 Last update: June 2002
 
 Philip Hazel
 Last update: June 2002

+
+(+undates July 2024, jgh)