Database handle destroyed without explicit disconnect

Tom Lane kindly steered me in the right direction to solve a physical disk drive problem after I posted my "'could not
readblock' error messages" message to this list on Jan. 8.  After correcting the hardware problem, the script that
wasn'tworking on Jan. 8 is now working.  Thank you, Mr. Lane, for your guidance.   

A new problem has now bubbled to the surface.  Another perl script that worked flawlessly for many years extracting
datafrom a PostgreSQL database and writing content to text files stopped working on Dec. 21.  When I run the script
manuallytoday, I receive this error message: 

DBD::Pg::db selectall_arrayref failed: server closed the connection unexpectedly at {script} line 692.
DBD::Pg::db selectall_arrayref failed: server closed the connection unexpectedly at {script} line 692.
Database handle destroyed without explicit disconnect.

Line 692 of the script says:

   my $ary_get = $dbhandle->selectall_arrayref($get);

The FreeBSD box hosting PostgreSQL shows this message in its /var/log/messages file everytime the script runs:

   Jan 27 14:07:11 midas /kernel: pid 36906 (postgres), uid 70: exited on signal 11 (core dumped)