Routers: named variables

1 files changed, 35 insertions, 0 deletions

diff --git a/doc/doc-docbook/spec.xfpt b/doc/doc-docbook/spec.xfpt
index b2f9dccc0..a073730c6 100644
--- a/doc/doc-docbook/spec.xfpt
+++ b/doc/doc-docbook/spec.xfpt
@@ -12759,6 +12759,16 @@ or if not set, the value of &$qualify_domain$&.
 .cindex queues named
 The name of the spool queue in use; empty for the default queue.
 
+.new
+.vitem &$r_...$&
+.vindex &$r_...$&
+.cindex router variables
+Values can be placed in these variables by the &%set%& option of a router.
+They can be given any name that starts with &$r_$&.
+The values persist for the address being handled through subsequent routers
+and the eventual transport.
+.wen
+
 .vitem &$rcpt_count$&
 .vindex "&$rcpt_count$&"
 When a message is being received by SMTP, this variable contains the number of
@@ -18078,6 +18088,10 @@ file = ${extract{mailbox}{$address_data}}
 This makes the configuration file less messy, and also reduces the number of
 lookups (though Exim does cache lookups).
 
+.new
+See also the &%set%& option below.
+.wen
+
 .vindex "&$sender_address_data$&"
 .vindex "&$address_data$&"
 The &%address_data%& facility is also useful as a means of passing information
@@ -18992,6 +19006,27 @@ SMTP VRFY command is enabled, it must be used after MAIL if the sender address
 matters.
 
 
+.new
+.option set routers string unset
+.cindex router variables
+This option may be used multiple times on a router.
+Each string given must be of the form $"name = value"$
+and the names used must start with the string &"r_"&.
+Strings are accumulated for each router which is run.
+When a router runs, the strings are evaluated in order,
+to create variables.
+The variable is set with the expansion of the value.
+The variables can be used by the router options
+(not including any preconditions)
+and by the transport.
+Later definitions of a given named variable will override former ones.
+Varible use is via the usual &$r_...$& syntax.
+
+This is similar to the &%address_data%& option, except that
+many independent variables can be used, with choice of naming.
+.wen
+
+
 .option translate_ip_address routers string&!! unset
 .cindex "IP address" "translating"
 .cindex "packet radio"