title: How to force Hadoop to unzip inputs regadless of their extension?
body: <p>I'm running map-reduce and my inputs are gzipped, but do not have a .gz (file name) extension. </p>
  
  <p>Normally, when they do have the .gz extension, Hadoop takes care of unzipping them on the fly before passing them to the mapper. However, without the extension it doesn't do so. I can't rename my files, so I need some way of "forcing" Hadoop to unzip them, even though they do not have the .gz extension. </p>
  
  <p>I tried  passing the following flags to Hadoop:</p>
  
  <p>step_args=[ "-jobconf", "stream.recordreader.compression=gzip",
                                       "-jobconf", "mapred.output.compress=true",
                                       "-jobconf", "mapred.output.compression.type=block",
                                       "-jobconf", "mapred.output.compression.codec=org.apache.hadoop.io.compress.GzipCodec"]</p>
  
  <p>However, the input to the mapper is still unzipped. I verified that by printing the inputs to the mapper inside the mapper code:</p>
  
  <p>mapper input: ^_^@%r?T^B??\K??6^R?+F?3^D??b?^R,??!???a?^X?A??n?m?k?3id?o?z[?-?L2yt^P$n?T,^V????^??y^O^R?nno>}^B^E^N-7?^Z?'?I?OF4??-^Z^X4;????f?RH???^Z?Q??4#^W?I?^F??^]?f+???f0d??A??v?A3*????7?x?p??7?Mq?.g??{^FL?g?^Y+?6??I????^V?C??I??$??ESCVd)K??}?Z??j?,3?{ ?}v???j???^??"?.??^L?^?LX^F??p???
  
  <p>Any advice on how to unzip on the fly would be greatly appreciated !</p>
  
  <p>Thanks!
  Gil. </p>