X-Git-Url: https://git.exim.org/users/jgh/exim.git/blobdiff_plain/a93dbf44ca97cc5e404ec6c889afd0a5f41c368a..08bd2689bdeceb41f161a7d54fc1af4abcbbb8c1:/doc/doc-txt/experimental-spec.txt

diff --git a/doc/doc-txt/experimental-spec.txt b/doc/doc-txt/experimental-spec.txt
index d51169073..481af1a9b 100644
--- a/doc/doc-txt/experimental-spec.txt
+++ b/doc/doc-txt/experimental-spec.txt
@@ -793,7 +793,12 @@ standard header.
 	Note that it would be wise to strip incoming messages of A-R headers
 	that claim to be from our own <admd-identifier>.
 
-There are two new variables: $arc_state and $arc_state_reason.
+There are three new variables: $arc_state, $arc_state_reason, $arc_domains:
+
+  $arc_state		One of pass, fail, none
+  $arc_state_reason	(if fail, why)
+  $arc_domains		colon-sep list of ARC chain domains, in chain order.
+			problematic elements may have empty list elements
 
 Receive log lines for an ARC pass will be tagged "ARC".
 
@@ -808,9 +813,15 @@ Expanded as a whole; if unset, empty or forced-failure then no signing is done.
 If it is set, all three elements must be non-empty.
 
 The fourth element is optional, and if present consists of a comma-separated list
-of options.  The only option implemented so far is
-  timestamps    Add a t= tag to the generated AMS and AS headers, with the
-                current time.
+of options.  The options implemented are
+
+  timestamps    	Add a t= tag to the generated AMS and AS headers, with the
+                	current time.
+  expire[=<val>]	Add an x= tag to the generated AMS header, with an expiry time.
+			If the value <val> is an plain number it is used unchanged.
+			If it starts with a '+' then the following number is added
+                	to the current time, as an offset in seconds.
+			If a value is not given it defaults to a one month offset.
 
 [As of writing, gmail insist that a t= tag on the AS is mandatory]