Documentation: describe subject more precisely

The discussion of email subject throughout the documentation is
misleading; it indicates that the first line will always become
the subject.  In fact, the subject is generally all lines up until
the first full blank line.

This patch refines that, and makes more use of the concept of a
commit title, with the title being all text up to the first blank line.

Signed-off-by: Jeremy White <jwhite@codeweavers.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 4 insertions, 3 deletions

diff --git a/Documentation/git-for-each-ref.txt b/Documentation/git-for-each-ref.txt
index c872b883ba..db55a4e0bb 100644
--- a/Documentation/git-for-each-ref.txt
+++ b/Documentation/git-for-each-ref.txt
@@ -102,9 +102,10 @@ Fields that have name-email-date tuple as its value (`author`,
 and `date` to extract the named component.
 
 The complete message in a commit and tag object is `contents`.
-Its first line is `contents:subject`, the remaining lines
-are `contents:body` and the optional GPG signature
-is `contents:signature`.
+Its first line is `contents:subject`, where subject is the concatenation
+of all lines of the commit message up to the first blank line.  The next
+line is 'contents:body', where body is all of the lines after the first
+blank line.  Finally, the optional GPG signature is `contents:signature`.
 
 For sorting purposes, fields with numeric values sort in numeric
 order (`objectsize`, `authordate`, `committerdate`, `taggerdate`).