loginitems-add

#!/usr/bin/osascript

on run (argv)
    set iname to (item 1 of argv)
    set ipath to (item 2 of argv)
    set ihide to (item 3 of argv)
    tell application "System Events"
        if (login item iname exists) is false then
            make login item at end with properties {name:iname, path:ipath, hidden:ihide}
        end if
    end tell
end run