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I have a file file.gz, when I try to unzip this file by using gunzip file.gz, it unzipped the file but only contains extracted and removes the file.gz file.

How can I unzip by keeping both unzipped file and zipped file?

PauloBoaventura
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jack
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2 Answers2

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Here are several alternatives:

  • Give gunzip the --keep option (version 1.6 or later)

    -k   --keep
            Keep (don't delete) input files during compression or decompression.

    gunzip -k file.gz

  • Pass the file to gunzip as stdin

    gunzip < file.gz > file

  • Use zcat (or, on older systems, gzcat)

    zcat file.gz > file
Mark Plotnick
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    Where do I get a version of gunzip with -k or --keep? I'm using version 1.5 in Gentoo and it has no such option. – Pavel Šimerda Sep 18 '14 at 22:02
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    @PavelŠimerda It was added in version 1.6. I've amended my answer. Thanks. – Mark Plotnick Sep 18 '14 at 22:15
  • Thanks a lot! With the other option this is now the best answer. – Pavel Šimerda Sep 18 '14 at 22:21
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    @PavelŠimerda If you need --keep but don't have it, just make a copy of file.gz first. – Liam Aug 19 '15 at 16:33
  • @Liam That's an ugly hack given that you need to copy it to a third unique file name and then move. And the answer already has a much better solution. – Pavel Šimerda Aug 19 '15 at 19:15
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    gunzip -c file.gz > file or zcat file.gz > file also work. https://superuser.com/questions/45650/how-do-you-gunzip-a-file-and-keep-the-gz-file/45651 – phyatt May 01 '17 at 14:38
  • What if there are more files in the .gz? – Pyjong Mar 29 '19 at 15:27
  • @Pyjong gunzip or zcat of a file containing multiple compressed streams will produce the concatenation of all the streams. cat thing1.gz thing2.gz > both.gz; gunzip -k both.gz will produce a single file named both and won't delete both.gz. The gzip man page recommends that, if you need to compress multiple flles while preserving all their names, you use something like tar to bundle them up and give tar the z option to gzip the entire bundle. – Mark Plotnick Mar 29 '19 at 18:51
  • gunzip doesn't have a -k option. Is this answer still valid?

    # gunzip -k my.gz gzip: invalid option -- 'k' Try 'gzip --help' for more information.

     – Worp May 03 '19 at 06:59
  • @Worp What is the output of gunzip --version ? The -k option is only in version 1.6 and beyond. – Mark Plotnick May 03 '19 at 08:43
  • fml, that makes sense. $ gunzip --version gunzip (gzip) 1.5 My bad, I will edit my comment! edit: I can't edit my comment anymore, so let's leave this up for clarification. Thanks for the info! – Worp May 03 '19 at 08:56
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Without requiring a temporary file:

 zcat somefile.gz > somefile
LatinSuD
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    This also works great if you want to pipe the output to another command with buffering without deleting the file zcat file.sql.gz | mysql --max_allowed_packet=32M db – Soheil Sep 19 '21 at 19:25