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I made two http calls to the same gzipped resource from two different machines - RHEL and OSX.


The first call returned an expected binary output:


The second call returned the content:

Hello, world!

The same phenomenon happened with wget - binary response from the RHEL machine, plaintext from the OSX one.

Could OSX be auto-opening my resource implicitly? Can I override these settings?

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up vote 3 down vote accepted

According to the OSX curl man page, some versions have automatic decompression of lzip encoded archives:

-V, --version
          Displays information about curl and the libcurl version it uses.

      The  third  line  (starts  with "Features:") shows specific features 
      libcurl reports to offer. Available features include:

      libz   Automatic decompression of compressed files over HTTP is supported.

So, I guess that if your run curl -V | grep libz on your OSX machine, you will see that it has this feature while the RHEL one does not.

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Thanks, that was it. Any idea how to disable? – Adam Matan Jun 13 '13 at 13:25
@AdamMatan not really, don't have a mac and my wget does not do this. You could try piping it through gzip: curl foo.gz | gzip > foo.gz. – terdon Jun 13 '13 at 13:30
@AdamMatan: I cannot test either... although my curl -V indicates that zlib is active, I doesn't gunzip automatically. But perhaps the --raw switch will help you: When used, it disables all internal HTTP decoding of content or transfer encodings and instead makes them passed on unaltered, raw. (Added in 7.16.2) – mpy Jun 13 '13 at 13:48

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