doc: glossary: add information for dates and timestamps

[public-inbox.git] / Documentation / public-inbox-glossary.pod

diff --git a/Documentation/public-inbox-glossary.pod b/Documentation/public-inbox-glossary.pod
index e188e563db12e5e042d3279b7cdd0a1483ab7eb4..61e1e9f8b1f777422ed8160779d3def9c67c2445 100644 (file)
--- a/Documentation/public-inbox-glossary.pod
+++ b/Documentation/public-inbox-glossary.pod
@@ -83,6 +83,20 @@ the same email into one or more virtual folders for
 ease-of-filtering.  This is NOT tied to public-inbox names, as
 messages stored by lei may not be public.
 
+=item IMAP INTERNALDATE, JMAP receivedAt, rt: search prefix
+
+The first valid timestamp value of Received: headers (top first).
+If no Received: header exists, the Date: header is used, and the
+current time if neither header(s) exist.  When mirroring via
+git, this is the git commit time.
+
+=item IMAP SENT*, JMAP sentAt, dt: and d: search prefixes
+
+The first valid timestamp value of the Date: header(s).
+If no Date: header exists, the time from the Received: header is
+used, and then the current time if neither header exists.
+When mirroring via git, this is the git author time.
+
 =head1 COPYRIGHT
 
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