Your first comment - at least one of the strings can get rather large - hence the desire to avoid local copies and all the associated memory wastage. The use of $! in the die statement - the next task is to write a suitable error routine - since this will be a CGI program, and I want a generic fatal error logger to write out a nice HTML page, complete with necessary debugging details for the user to forward to the webmaster.
Thanks again for pointing out my error - one should never try to read perlref late in the evening.