The error usually sits in front of the computer, even though the perl
documentation could be a bit more explicit about this:
I just had to modify my little script to contain -emacs like:
cat /tmp/stdin-17959.log | perl -d
A perldoc perl5db.pl tells you under 'SETTING UP THE TERMINAL' to
specify -emacs as the first option after the script.
If there is a TTY, we have to determine who it belongs to before
proceed. If this is a slave editor or graphical debugger (denoted by
the first command-line switch being '-emacs'), we shift this off and
set $rl to 0 (XXX ostensibly to do straight reads).