if(-T $file) {
    print "$file is an ascii text file \n";
} else {
    print "Not an ascii text file \n";
}

##</code><code>##


    my $ft           = File::Type->new();
    my $type         = $ft->mime_type($file);

    if ( $type eq "application/octet-stream" ) {
        do this..
    } else {
        do that..
    }