> Is there any robust and convenient methods for me to obtain the lua script's (absolute/real) dirname and file name from within the script itself?
Your question is not well defined. Lua can load and execute a string that resides entirely in memory without ever been stored in a file - is that a script? A Lua chunk can load and run another chunk, etc, some of which may or may not file based - what is "the script" in this case? Unless you indicate exactly what your "script" is, you are not going to get an unambiguous answer.
Cheers,
V.
