GNU Info

(gnus)Headers

---

Next: Ranges Prev: Score File Syntax Up: Gnus Reference Guide

---

Enter node , (file) or (file)node

Headers
-------

   Internally Gnus uses a format for storing article headers that
corresponds to the NOV format in a mysterious fashion.  One could
almost suspect that the author looked at the NOV specification and just
shamelessly _stole_ the entire thing, and one would be right.

   "Header" is a severely overloaded term.  "Header" is used in RFC
1036 to talk about lines in the head of an article (e.g., `From').  It
is used by many people as a synonym for "head"--"the header and the
body".  (That should be avoided, in my opinion.)  And Gnus uses a
format internally that it calls "header", which is what I'm talking
about here.  This is a 9-element vector, basically, with each header
(ouch) having one slot.

   These slots are, in order: `number', `subject', `from', `date',
`id', `references', `chars', `lines', `xref', and `extra'.  There are
macros for accessing and setting these slots--they all have predictable
names beginning with `mail-header-' and `mail-header-set-',
respectively.

   All these slots contain strings, except the `extra' slot, which
contains an alist of header/value pairs (Note: To From Newsgroups).