How to Fix “tar: Archive is compressed. Use -z option” Error in Linux

If you are working with tar archives in Linux, you may encounter an error message like this:

tar: Archive is compressed. Use -z option

This error usually happens when you try to extract or list the contents of a tar archive that is compressed with gzip, but you forget to use the -z option. For example, if you run this command:

cat archive.tar.gz | tar tf -

You will get the error message because you are piping the compressed archive to tar without telling it to decompress it first. The -z option tells tar to filter the archive through gzip before processing it.

How to Solve the Error

The solution is simple: just add the -z option to your tar command. For example, if you want to extract the archive, you can run this command:

cat archive.tar.gz | tar xzf -

Or, if you want to list the contents of the archive, you can run this command:

cat archive.tar.gz | tar tzf -

Alternatively, you can also use the -a option, which tells tar to automatically detect the compression type of the archive and use the appropriate filter. For example, you can run this command:

cat archive.tar.gz | tar af -

This will work for any compression type that tar supports, such as gzip, bzip2, xz, etc.

Why You Need to Use the -z Option

You may wonder why you need to use the -z option when tar can recognize gzip compression automatically when reading archives from a file. For example, if you run this command:

tar tf archive.tar.gz

You will not get any error message and tar will list the contents of the archive correctly.

The reason is that when you read an archive from a file, tar can use random access to read the file header and determine the compression type. However, when you read an archive from a pipe or a tape drive that does not support random access, tar cannot do that and needs you to specify the compression type explicitly.

Frequently Asked Questions

Here are some common questions and answers related to this topic:

Q: How do I create a compressed tar archive?

A: To create a compressed tar archive, you need to use the -c option to create a new archive and the -z option to compress it with gzip. For example, if you want to create a compressed archive of a directory called mydir, you can run this command:

tar czf mydir.tar.gz mydir

This will create a file called mydir.tar.gz that contains all the files and subdirectories of mydir.

Q: How do I decompress a compressed tar archive?

A: To decompress a compressed tar archive, you need to use the -x option to extract the files and the -z option to decompress it with gzip. For example, if you want to extract a compressed archive called mydir.tar.gz, you can run this command:

tar xzf mydir.tar.gz

This will extract all the files and subdirectories of mydir in the current directory.

Q: How do I list the contents of a compressed tar archive?

A: To list the contents of a compressed tar archive, you need to use the -t option to list the files and the -z option to decompress it with gzip. For example, if you want to list the contents of a compressed archive called mydir.tar.gz, you can run this command:

tar tzf mydir.tar.gz

This will print the names of all the files and subdirectories of mydir in the standard output.

Conclusion

In this article, we have learned how to fix the “tar: Archive is compressed. Use -z option” error in Linux by using the -z option or the -a option with tar. We have also learned why we need to use these options when reading archives from pipes or tape drives that do not support random access.

We hope this article was helpful for you. If you have any questions or feedback, please leave a comment below.