how to keep one instance???

Tue May 18 03:31:46 EDT 2004

Hi,
    can anyone tell me how to keep only one instance in memory? I write a python script,an editor, so if user click the .txt files, it will run. But if user click the same .txt file again , user will get another instance. So, how to prevent the other instance from running?
and how could the second instance pass some information to the first one?
    Any helps are appreciated.

　　　　　　　　BruceKL WhoH
　　　　　　　　BruceWhoHKL at gawab.com
　　　　　　　　　　2004-05-18