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, 2 deletions

diff --git a/Documentation/git-commit.txt b/Documentation/git-commit.txt
index 4622297ec9..9594ac8e9d 100644
--- a/Documentation/git-commit.txt
+++ b/Documentation/git-commit.txt
@@ -389,8 +389,10 @@ DISCUSSION
 Though not required, it's a good idea to begin the commit message
 with a single short (less than 50 character) line summarizing the
 change, followed by a blank line and then a more thorough description.
-Tools that turn commits into email, for example, use the first line
-on the Subject: line and the rest of the commit in the body.
+The text up to the first blank line in a commit message is treated
+as the commit title, and that title is used throughout git.
+For example, linkgit:git-format-patch[1] turns a commit into email, and it uses
+the title on the Subject line and the rest of the commit in the body.
 
 include::i18n.txt[]