use strict;
use FileHandle;
use IO::Compress::Gzip;

my $unicode_string = "Smiley Face: \x{263A}\n";

writefile({
    'filename'  => "/tmp/out",
    'gzip'      => 0,
    'data'      => $unicode_string,
});

writefile({
    'filename'  => "/tmp/out.gz",
    'gzip'      => 1,
    'data'      => $unicode_string,
});

sub writefile {
    my($opts) = @_;

    my $fh = ($opts->{'gzip'}) ?
        IO::Compress::Gzip->new(
            FileHandle->new("> $opts->{'filename'}"),
        ) :
        FileHandle->new("> $opts->{'filename'}");

    binmode($fh, ':utf8');

    print $fh $opts->{'data'};
    $fh->close;
}

__DATA__
[download]

First subroutine call succeeds and produces a /tmp/out file with the expected content.

Seoond subroutine call fails with the message:
Wide character in IO::Compress::Gzip::write: at <program_name> line 29.

Line 29 is the 'print' statement.

Documentation suggests IO::Compress::Gzip::binmode is a no-op.

Using "Encode::decode_utf8($opts->{'data'});" doesn't work either.

The second subroutine call produces a valid, compressed as expected /tmp/out.gz file as long as $unicode_string doesn't actually contain any unicode characters.

How do I make this work? I'd much prefer to compress in perl rather than gzip files after writing them, as the real-world code with the issue demonstrated by this minimum-reproducible test case deals with large data volumes and performance is a concern.

2018-03-03 Athanasius removed the question text from the main code block and added paragraph tags

---

In reply to IO::Compress::Gzip and unicode by Anonymous Monk

Title:
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