Memory Problem?

[Peter Reid]

I've a program written in Rev 2.7.4 running under Max OS X 10.3.9  
Server which copies 50+ backup files from one partition of a FireWire  
drive to another using the revCopyFile command.  The size of each  
backup file varies from 350Mb up to 7Gb.  During the copy process a  
log is written to a text file, showing the start time of the session,  
the details of each file copied and the end time of the session.   
Each file is copied one after another with the log entry being added  
after each file has been copied.  The program always copies all files  
and the log file is complete with both session start and end time.   
However, once the copying is finished (taking some 90 minutes or so  
overnight), my Rev program is now frozen, not responding to any mouse  
clicks or attempts to open any of its menus (the Mac is otherwise  
working OK, no other problems with any other running programs).  This  
means using the Apple menu "Force Quit..." after every run of the  
program.  This program is supposed to run in the background all the  
time monitoring other activities and then doing the copying of the  
backup files overnight, but can't be used this way as it's always  
frozen after the copying!!

I deliberately used the revCopyFile command instead of the put URL  
command because of the advantages listed on the Rev help:

> However, the revCopyFile command provides certain advantages. It  
> copies file attributes (such as file type) and Mac OS resource  
> forks along with the file. It also does not require reading the  
> entire file into memory, so even extremely large files can be copied.

According to the above from the help, memory shouldn't be a problem.   
However, the symptoms seem to be of a memory problem.

Any suggestions please?