set PWD in Lion Terminal.app from screen

snippet.sh

# Screen-compatible update_terminal_cwd()
update_terminal_cwd() {
    # Identify the directory using a "file:" scheme URL,
    # including the host name to disambiguate local vs.
    # remote connections. Percent-escape spaces.
    local SEARCH=' '
    local REPLACE='%20'
    local PWD_URL="file://$HOSTNAME${PWD//$SEARCH/$REPLACE}"
    # Include the escapes needed for screen to forward to Terminal.app
    printf '\eP\e]7;%s\a\e\\' "$PWD_URL"
}