Instead of running the Tcl code really embedded inside your Perl code, you might want to just launch the Tcl interpreter with the script and capture the output. The simplest approach would be:

my $script = 'my_script.tcl';
system($script) == 0
    or die "Couldn't launch '$script': $! / $?";
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If you want to capture the output of your script, use backticks:

my @lines = `$script`;
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There are many other ways, like Open2 and Open3, depending on whether you need to talk to the Tcl script or need to separate the output streams.