Well, here is a way to avoid the temp file, not in the docs but it works.

#!/usr/bin/perl
use warnings;
use strict;
use Crypt::DSA;
use Crypt::DSA::Key;

my $dsa = Crypt::DSA->new;

my $key = $dsa->keygen(Size => 512, Verbosity => 1);

my $pem = $key->write( Type => 'PEM');
print "pem-> $pem\n";

my $sig_msg = 'yadda yaddax yadda';

my $key1 = Crypt::DSA::Key->new( Type=>'PEM', Content => $pem );
print "$key1\n";

my $sig = $dsa->sign(Message=>$sig_msg, Key => $key1 );
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