Documentation: Correct alternates documentation, document http-alternates

For one, the documentation invalidly claimed that the paths have to be
absolute when that's not the case and in fact there is a very valid reason
not to use absolute paths (documented the reason as well).

Signed-off-by: Petr Baudis <pasky@suse.cz>
Signed-off-by: Junio C Hamano <junkio@cox.net>

diff --git a/Documentation/repository-layout.txt b/Documentation/repository-layout.txt
index 6d8c58ed205cb051cf2a1f8f495d37405cabd398..e20fb7e74c22390e810a392f2625a3ba6b325477 100644 (file)
--- a/Documentation/repository-layout.txt
+++ b/Documentation/repository-layout.txt
@@ -52,9 +52,20 @@ objects/info/packs::
        by default.
 
 objects/info/alternates::
-       This file records absolute filesystem paths of alternate
-       object stores that this object store borrows objects
-       from, one pathname per line.
+       This file records paths to alternate object stores that
+       this object store borrows objects from, one pathname per
+       line. Note that not only native Git tools use it locally,
+       but the HTTP fetcher also tries to use it remotely; this
+       will usually work if you have relative paths (relative
+       to the object database, not to the repository!) in your
+       alternates file, but it will not work if you use absolute
+       paths unless the absolute path in filesystem and web URL
+       is the same. See also 'objects/info/http-alternates'.
+
+objects/info/http-alternates::
+       This file records URLs to alternate object stores that
+       this object store borrows objects from, to be used when
+       the repository is fetched over HTTP.
 
 refs::
        References are stored in subdirectories of this