http://qs321.pair.com?node_id=11115125


in reply to Re^2: Lost in compressed encodings
in thread Lost in compressed encodings

I think that IO::Uncompress::Gunzip only understands ->binmode() and not ->binmode(':utf8');. The documentation (now that I read it ...) even says:

This is a noop provided for completeness.

If you are able to install PerlIO::gzip, that one should work with stacking other decoding mechanisms on top of it.

If you have a gzip binary available, you can use that to decompress:

my $in;
if( $filename =~ /\.gz$/ ) {
    open $fh, "gzip -cd "$filename" |'
        or die "Can't read from gzip $filename: $!/$?";
} else {
    open $in, '<:raw', $filename or die "Can't read $filename: $!\n";
};
binmode $fh, ':utf8';

[download]

Replies are listed 'Best First'.
Re^4: Lost in compressed encodings
by Skeeve (Parson) on Apr 06, 2020 at 09:19 UTC

    Thanks for all your suggestions, Corion.

    As my usecase is a module which reads a (kind of) CSV file, there are just 2 places, where I read a line from the file.

    So I decied to do the "manual" decoding: 

    open my $in, '<:raw', $filename or die "Can't read $filename: $!\n";
if ($filename=~/\.gz$/) {
    $in= new IO::Uncompress::Gunzip $in, { AutoClose => 1 };
}
# later on
$_= <$in>;
chomp;
@headers= split /\t/, lc decode('UTF-8' => $_);
# That's not really required as the header will always be
# ASCII-characters… But for completeness sake…

# further down I have a loop
while (<$in>) {
    chomp;
    # …
    @line{@headers}= split /\t/, decode('UTF-8' => $_);

    [download]
    s$$([},&%#}/&/]+}%&{})*;#$&&s&&$^X.($'^"%]=\&(|?*{%
    +.+=%;.#_}\&"^"-+%*).}%:##%}={~=~:.")&e&&s""`$''`"e
[reply]
[d/l]
[select]

      I would suggest using Text::CSV_XS to read/parse the CSV. It already knows how to deal with UTF-8.

      It is capable of using a TAB as separation character:

      use Text::CSV_XS;

my $csv = Text::CSV_XS->new ({ binary => 1, sep_char => "\t", auto_dia
+g => 1 });
my @headers = $csv->header ($in); # Read the docs, there are options p
+ossible here
while (my $row = $csv->getline ($in)) {
    # ...
    }

      [download]

      update: I realized later that Text::CSV_XS' csv function already supports gzip as part of the encoding attribute.

      use Text::CSV_XS qw( csv );
use PerlIO::via::gzip;

my $aoa = csv (in => "test.csv.gz",  encoding => ":via(gzip)");

      [download]

      Enjoy, Have FUN! H.Merijn
[reply]
[d/l]
[select]

In Section Seekers of Perl Wisdom