## In a different session from which I will run my modified version of your script
C:\test>echo xx > ttz
C:\test>handle | find "ttz"  ## shows that immediately after creation, nothing has an open handle to that file

## Now in the other session
C:\test>junk44
Permission denied : The process cannot access the file because it is being used by another process at C:\test\junk44.pl line 12.

## And back in the first session whilst the 10 second sleep is running
C:\test>handle | find "ttz"
   60: File  (RW-)   C:\test\ttz