1#!/bin/sh23. git-sh-setup-script || die "Not a git archive"45branchname="$1"6case "$2" in7'')8head=HEAD ;;9*)10head="$2^0" ;;11esac12rev=$(git-rev-parse --revs-only --verify "$head") || exit1314[ -z "$branchname" ] && die "git branch: I want a branch name"15[ -e "$GIT_DIR/refs/heads/$branchname" ] && die "$branchname already exists"1617echo $rev > "$GIT_DIR/refs/heads/$branchname"