document backend selection

1 files changed, 15 insertions, 6 deletions

diff --git a/antispam.7 b/antispam.7
index 5544ca3..c08af34 100644
--- a/antispam.7
+++ b/antispam.7
@@ -61,7 +61,7 @@ protocol imap {
 
 .SH BACKENDS
 
-The plugin supports multiple backends, there are currently two working
+The plugin supports multiple backends, there are currently a few working
 backends included in the distribution:
 
 .SS dspam executable backend (dspam specific)
@@ -71,12 +71,13 @@ problems with this approach including
 (1) it can take a long time during which the IMAP session is blocked
 (2) when many users retrain many messages at once server load may spike
 
-.SS email sender backend (spam filter agnostic)
+.SS pipe backend (spam filter agnostic)
 
-This backend sends mail to ham@example.com or spam@example.com
-(actual addresses are configurable) for retraining. This backend can
-be very fast to set up if you already have a working setup that uses
-training addresses as recommended by many spam filter setups.
+This backend simply pipes the mail to train to a process it executes.
+This can for example be used to send it as email to mail aliases for
+retraining. This backend can be very easy to set up if you already
+have a working setup that uses training addresses as recommended by
+many spam filter setups.
 
 Since this backend simply pipes the message to a program (by default
 sendmail) it can also be used for all kinds of other spam filters,
@@ -111,6 +112,14 @@ plugin {
     ##################
     # GENERIC OPTIONS
 
+    # backend selection, MUST be configured first,
+    # there's no default so you need to set one of
+    # these options:
+    # antispam_backend = crm114-exec
+    # antispam_backend = dspam-exec
+    # antispam_backend = pipe
+    # antispam_backend = spool2dir
+
     # mail signature (used with any backend requiring a signature)
     antispam_signature = X-DSPAM-Signature