From: Jeremy Harris <jgh146exb@wizmail.org>
Date: Sat, 16 May 2020 18:38:59 +0000 (+0100)
Subject: Docs: options on lookups
X-Git-Url: https://git.exim.org/users/heiko/exim.git/commitdiff_plain/a63442492d25b3ab12d0bce2a8b879e32855aa72

Docs: options on lookups
---

diff --git a/doc/doc-docbook/spec.xfpt b/doc/doc-docbook/spec.xfpt
index 6d8582528..12c03df64 100644
--- a/doc/doc-docbook/spec.xfpt
+++ b/doc/doc-docbook/spec.xfpt
@@ -6663,6 +6663,13 @@ If the value of &$sender_host_address$& is 192.168.5.6, expansion of the
 first &%domains%& setting above generates the second setting, which therefore
 causes a second lookup to occur.
 
+.new
+The lookup type may optionally be followed by a comma
+and a comma-separated list of options.
+Each option is a &"name=value"& pair.
+Whether an option is meaningful depands on the lookup type.
+.wen
+
 The rest of this chapter describes the different lookup types that are
 available. Any of them can be used in any part of the configuration where a
 lookup is permitted.
@@ -6680,6 +6687,13 @@ lookup to succeed. The lookup type determines how the file is searched.
 .new
 .cindex "tainted data" "single-key lookups"
 The file string may not be tainted
+
+.cindex "tainted data" "de-tainting"
+All single-key lookups support the option &"ret=key"&.
+If this is given and the lookup
+(either underlying implementation or cached value)
+returns data, the result is replaced with a non-tainted
+version of the lookup key.
 .wen
 .next
 .cindex "query-style lookup" "definition of"
diff --git a/src/src/lookups/README b/src/src/lookups/README
index dad69dcc0..2e87edadd 100644
--- a/src/src/lookups/README
+++ b/src/src/lookups/README
@@ -135,6 +135,8 @@ DEFER. The arguments are:
                       If set to a nonzero number of seconds, the cached value
                       becomes unusable after this time. Currently the dnsdb
                       lookup uses this to support the TTL value.
+  uschar *opts	      options, a comma-separated list of tagged values for
+                      modifying the search operation
 
 Even though the key is zero-terminated, the length is passed because in the
 common case it has been computed already and is often needed.