[Mimedefang] BIG problems with mimedefang

[WBrown at e1b.org]

mimedefang-bounces at lists.roaringpenguin.com wrote on 01/19/2006 12:30:47 
PM:

> 3) Atomically rename database.db.new to database.db

Can you enlightne me on what "Atomically rename" means?  How is that 
different than just a mv command.  I can understand that a process that 
opened the file under the old name is still going to point to the file 
based on its location on disk, not by name.  I'm just picturing mushroom 
clouds and guys in lead hazmat suits trying to do an atomic rename. :)