[PATCH] Teach git-remote to update existing remotes by fetching from them

@@ -439,6 +439,10 @@ pull.octopus::
 pull.twohead::
 	The default merge strategy to use when pulling a single branch.
 
+remote.fetch::
+	The list of remotes which are fetched by "git remote update".
+	See gitlink:git-remote[1].
+
 remote.<name>.url::
 	The URL of a remote repository.  See gitlink:git-fetch[1] or
 	gitlink:git-push[1].

@@ -13,6 +13,7 @@ SYNOPSIS
 'git-remote' add <name> <url>
 'git-remote' show <name>
 'git-remote' prune <name>
+'git-remote' update
 
 DESCRIPTION
 -----------

@@ -40,7 +41,14 @@ Gives some information about the remote <name>.
 
 Deletes all stale tracking branches under <name>.
 These stale branches have already been removed from the remote repository
-referenced by <name>, but are still locally available in "remotes/<name>".
+referenced by <name>, but are still locally available in
+"remotes/<name>".
+
+'update'::
+
+Fetch updates for the remotes in the repository.  By default all remotes
+are updated, but this can be configured via the configuration parameter 
+'remote.fetch'.   (See gitlink:git-config[1]).
 
 
 DISCUSSION

@@ -303,6 +303,18 @@ elsif ($ARGV[0] eq 'show') {
 		show_remote($ARGV[$i], $ls_remote);
 	}
 }
+elsif ($ARGV[0] eq 'update') {
+        my $conf = $git->config("remote.fetch");
+	if (defined($conf)) {
+	    	@remotes = split(' ', $conf);
+	} else {
+	        @remotes = sort keys %$remote;
+	}
+	for (@remotes) {
+		print "Fetching $_\n";
+		$git->command('fetch', "$_");
+	}
+}
 elsif ($ARGV[0] eq 'prune') {
 	my $ls_remote = 1;
 	my $i;

@@ -360,5 +372,6 @@ else {
 	print STDERR "       git remote add <name> <url>\n";
 	print STDERR "       git remote show <name>\n";
 	print STDERR "       git remote prune <name>\n";
+	print STDERR "       git remote update\n";
 	exit(1);
 }