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From: Robert Klemme <shortcutter@googlemail.com>
Newsgroups: comp.lang.ruby
Subject: Re: Zlib::GzipReader doesn't work as expected
Date: Wed, 25 Apr 2012 21:03:44 +0200
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Xref: csiph.com comp.lang.ruby:6518

On 04/25/2012 10:57 AM, Thomas Wolf wrote:
> Hi,
> given 2 files:
> cat 5lines.txt
> 5 lines
> 5 lines
> 5 lines
> 5 lines
> 5 lines
>
> cat more5lines.txt
> More 5 lines
> More 5 lines
> More 5 lines
> More 5 lines
> More 5 lines
>
> These files are "gzip"ed as follows:
> gzip < 5lines.txt > foo.gz
> gzip < more5lines.txt >> foo.gz
>
> zcat foo.gz:
> 5 lines
> 5 lines
> 5 lines
> 5 lines
> 5 lines
> More 5 lines
> More 5 lines
> More 5 lines
> More 5 lines
> More 5 lines
>
> This ruby code only reads the first 5 lines:
> #!/usr/bin/ruby
> require "zlib"
> filename = ARGV[0]
>
> Zlib::GzipReader.open(filename) {|gz|
> print gz.read
> }
>
> ./test.rb foo.gz
> 5 lines
> 5 lines
> 5 lines
> 5 lines
> 5 lines
>
> How do I force Zlib::GzipReader do read the whole file?

That's a fairly common limitation of GZip libs (Java's standard lib also 
has this limitation, or at least hat last time I checked).

You might get away with wrapping the GzipReader around an open IO object 
and wrapping another GzipReader when the first finishes.

Kind regards

	robert