my $digest = print $ctx->hexdigest, "\n";

That code will result in $digest having a value of 1. That's probably not what you meant.

$ perl -e '
> use Digest::MD5;
> $ctx = Digest::MD5->new();
> open FILE, q{<}, q{xxx} or die $!;
> $ctx->addfile( *FILE );
> $digest = print $ctx->hexdigest(), qq{\n};
> print qq{-->$digest<--\n};'
cc88f0aa880a1b97b84bfd0ebc420fa7
-->1<--
$
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I hope this is useful.