Thank you... Interestingly, when I use this code: 
use warnings;
use strict;
use CGI;

use Data::Dumper;
print "Content-type: text/html\n\n";

my $cgi = CGI->new();
my %params = map { $_ => $cgi->param($_) || '' } $cgi->param;

print Dumper \%params;

[download]
The output is when I pass test.pl?a=\'b is: 
$VAR1 = { 'a' => '\\\'b' };

[download]
... so it looks like something in the stack is already taking care of the escaping for me. Am I worrying about nothing?

In reply to Re^2: Escaping %params by DaisyLou
in thread Escaping %params by DaisyLou

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