Comments by Lucian Todor (Top 1 by date)

It is recommended for the temporary file to use the "lock file" mechanism.
Create lock file, use resource, unlock.

See
LockFile - for windows
http://msdn.microsoft.com/en-us/library/windows/desktop/aa365202%28v=vs.85%29.aspx

flock - for linux
http://linux.die.net/man/2/flock