PerlIO::gzip can't handle appended stuff

[Skeeve]

I'm wondering what I'm missing.

Every hour I receive a bunch of data which I write into a compressed (gzip) text file.

I collect all the 24 data deliveries into one file by simply appending to the file created in the first hour.

When I do a gunzip -c myfile.gz I can see all my data.

Whenn I open the same file with PerlIO::gzip I only get the first set of data.

Here is a small script to reproduce:

use PerlIO::gzip;
open my $out, ">:gzip", "tst.gz";
print $out "111111111111111111111111\n" x 100;
close $out;
open my $out, ">>:gzip", "tst.gz";
print $out "222222222222222222222222\n" x 100;
close $out;

open my $in, "<:gzip", "tst.gz";
print while <$in>;
close $in;

Question is: How can I convince perl to continue reading data?

[haukex]

AFAICT from Bug #90480, I think PerlIO::gzip may not support this. I usually use the core modules IO::Compress::* and IO::Uncompress::*. Their objects can also be used like filehandles - this works for me:

use IO::Uncompress::Gunzip ();
my $in = IO::Uncompress::Gunzip->new('tst.gz', MultiStream=>1 )
    or die "$IO::Uncompress::Gunzip::GunzipError";
print while <$in>;
close $in;

[Skeeve]

I already tried that as well and it also just prints the first part.

It works! Thanks!

Just have to add Multistream like so:

my $in = new IO::Uncompress::Gunzip "tst.gz", Multistream => 1
    or die "IO::Uncompress::Gunzip failed: $GunzipError\n";
print while <$in>;