Super User is a question and answer site for computer enthusiasts and power users. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I am running knoppix through a bootable cd. I tried to extract a .tar.gz with the following command.

tar -xvzf demo.tar.gz 

and i am getting this error.

gzip: stdin: not in gzip format tar: Child returned status 1 tar: Error is not recoverable: exiting now

is there any other way to extract the files?

share|improve this question

migrated from Dec 28 '12 at 20:23

This question came from our site for professional and enthusiast programmers.

(A bit late for the OP, but here it goes...)

gzip said it: it is not a gzip-compressed archive. I can think of a few alternatives:

  • The filename is misleading and the file is already uncompressed - that occasionally happens when a file is downloaded using some browsers from specific servers; the browser will uncompress the file on its own without altering the its name.

  • The filename is misleading and the file is compressed with some other method. Use the file command to find out what the content of the file is - it should tell you if it has been compressed with another method.

  • The file is corrupt and gzip cannot recover. There are about a million different reasons for this to happen, from solar flares to incomplete downloads to wget downloading an HTML error or redirection page, rather than the file itself. You will have to procure another copy of the file...

share|improve this answer
One simple reason could be a defective burned cd, I had that several times with very cheap CD-R. – ott-- Dec 28 '12 at 21:03

You must log in to answer this question.