You pasted together some snippets of the CGI documentation, but all of those snippets are supposed to be used separately, not together. Personally, I would use the upload() variant:

    my $original_name = param('uploaded_file');
    my $fh = upload('uploaded_file');
    binmode $fh; # just to be sure

    # "Untaint" the original name:
    $original_name =~ s/[^\w.]/_/g;

    my $outname = File::Spec->catfile( $private_dir, $original_name );
    open my $outfile, '>', $outname
        or die "Couldn't create $outname: $!";

    local $/ = \4096; # blocksize
    while (<$fh>) {
          print $outfile $_;
    };

    warn "Uploaded a file into $outname";

[download]

Update: Corrected local $/ = \4096, as spotted by cdarke

In reply to Re: After Revieing the Cpan On CGI, wrt Uploading things by Corion
in thread A Journey in Uploading by barrycarlyon

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