On Unix platform, tar command is the primary archiving utility. Understanding various tar command options will help you master the archive file manipulation.
In this article, let us review various tar examples including how to create tar archives (with gzip and bzip compression), extract a single file or directory, view tar archive contents, validate the integrity of tar archives, finding out the difference between tar archive and file system, estimate the size of the tar archives before creating it etc.,
1. Creating an archive using tar command
Creating an uncompressed tar archive using option cvf
This is the basic command to create a tar archive.
$ tar cvf archive_name.tar dirname/
In the above command:
- c – create a new archive
- v – verbosely list files which are processed.
- f – following is the archive file name
Creating a tar gzipped archive using option cvzf
The above tar cvf option, does not provide any compression. To use a gzip compression on the tar archive, use the z option as shown below.
$ tar cvzf archive_name.tar.gz dirname/
- z – filter the archive through gzip
Note: .tgz is same as .tar.gz
Note: I like to keep the ‘cvf’ (or tvf, or xvf) option unchanged for all archive creation (or view, or extract) and add additional option at the end, which is easier to remember. i.e cvf for archive creation, cvfz for compressed gzip archive creation, cvfj for compressed bzip2 archive creation etc., For this method to work properly, don’t give – in front of the options.
Creating a bzipped tar archive using option cvjf
Create a bzip2 tar archive as shown below:
$ tar cvfj archive_name.tar.bz2 dirname/
- j – filter the archive through bzip2
gzip vs bzip2: bzip2 takes more time to compress and decompress than gzip. bzip2 archival size is less than gzip.
Note: .tbz and .tb2 is same as .tar.bz2
2. Extracting (untar) an archive using tar command
Extract a *.tar file using option xvf
Extract a tar file using option x as shown below:
$ tar xvf archive_name.tar
- x – extract files from archive
Extract a gzipped tar archive ( *.tar.gz ) using option xvzf
Use the option z for uncompressing a gzip tar archive.
$ tar xvfz archive_name.tar.gz
Extracting a bzipped tar archive ( *.tar.bz2 ) using option xvjf
Use the option j for uncompressing a bzip2 tar archive.
$ tar xvfj archive_name.tar.bz2
Note: In all the above commands v is optional, which lists the file being processed.
3. Listing an archive using tar command
View the tar archive file content without extracting using option tvf
You can view the *.tar file content before extracting as shown below.
$ tar tvf archive_name.tar
View the *.tar.gz file content without extracting using option tvzf
You can view the *.tar.gz file content before extracting as shown below.
$ tar tvfz archive_name.tar.gz
View the *.tar.bz2 file content without extracting using option tvjf
You can view the *.tar.bz2 file content before extracting as shown below.
$ tar tvfj archive_name.tar.bz2
4. Listing out the tar file content with less command
When the number of files in an archive is more, you may pipe the output of tar to less. But, you can also use less command directly to view the tar archive output, as explained in one of our previous article Open & View 10 Different File Types with Linux Less Command — The Ultimate Power of Less.
5. Extract a single file from tar, tar.gz, tar.bz2 file
To extract a specific file from a tar archive, specify the file name at the end of the tar xvf command as shown below. The following command extracts only a specific file from a large tar file.
$ tar xvf archive_file.tar /path/to/file
Use the relevant option z or j according to the compression method gzip or bzip2 respectively as shown below.
$ tar xvfz archive_file.tar.gz /path/to/file $ tar xvfj archive_file.tar.bz2 /path/to/file
6. Extract a single directory from tar, tar.gz, tar.bz2 file
To extract a single directory (along with it’s subdirectory and files) from a tar archive, specify the directory name at the end of the tar xvf command as shown below. The following extracts only a specific directory from a large tar file.
$ tar xvf archive_file.tar /path/to/dir/
To extract multiple directories from a tar archive, specify those individual directory names at the end of the tar xvf command as shown below.
$ tar xvf archive_file.tar /path/to/dir1/ /path/to/dir2/
Use the relevant option z or j according to the compression method gzip or bzip2 respectively as shown below.
$ tar xvfz archive_file.tar.gz /path/to/dir/ $ tar xvfj archive_file.tar.bz2 /path/to/dir/
7. Extract group of files from tar, tar.gz, tar.bz2 archives using regular expression
You can specify a regex, to extract files matching a specified pattern. For example, following tar command extracts all the files with pl extension.
$ tar xvf archive_file.tar --wildcards '*.pl'
Options explanation:
- –wildcards *.pl – files with pl extension
8. Adding a file or directory to an existing archive using option -r
You can add additional files to an existing tar archive as shown below. For example, to append a file to *.tar file do the following:
$ tar rvf archive_name.tar newfile
This newfile will be added to the existing archive_name.tar. Adding a directory to the tar is also similar,
$ tar rvf archive_name.tar newdir/
Note: You cannot add file or directory to a compressed archive. If you try to do so, you will get “tar: Cannot update compressed archives” error as shown below.
$ tar rvfz archive_name.tgz newfile tar: Cannot update compressed archives Try `tar --help' or `tar --usage' for more information.
9. Verify files available in tar using option -W
As part of creating a tar file, you can verify the archive file that got created using the option W as shown below.
$ tar cvfW file_name.tar dir/
If you are planning to remove a directory/file from an archive file or from the file system, you might want to verify the archive file before doing it as shown below.
$ tar tvfW file_name.tar Verify 1/file1 1/file1: Mod time differs 1/file1: Size differs Verify 1/file2 Verify 1/file3
If an output line starts with Verify, and there is no differs line then the file/directory is Ok. If not, you should investigate the issue.
Note: for a compressed archive file ( *.tar.gz, *.tar.bz2 ) you cannot do the verification.
Finding the difference between an archive and file system can be done even for a compressed archive. It also shows the same output as above excluding the lines with Verify.
Finding the difference between gzip archive file and file system
$ tar dfz file_name.tgz
Finding the difference between bzip2 archive file and file system
$ tar dfj file_name.tar.bz2
10. Estimate the tar archive size
The following command, estimates the tar file size ( in KB ) before you create the tar file.
$ tar -cf - /directory/to/archive/ | wc -c 20480
The following command, estimates the compressed tar file size ( in KB ) before you create the tar.gz, tar.bz2 files.
$ tar -czf - /directory/to/archive/ | wc -c 508 $ tar -cjf - /directory/to/archive/ | wc -c 428
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My name is Ramesh Natarajan. I will be posting instruction guides, how-to, troubleshooting tips and tricks on Linux, database, hardware, security and web. My focus is to write articles that will either teach you or help you resolve a problem. Read more about 
{ 14 comments… read them below or add one }
You missed few really useful examples, like ie.
tar cjf archive-$(date +%Y%m%d).tbz2 dir/
tar cjf archive-$(date +%Y%m%d).tbz2 dir/ -N ./archive-$(date -d yesterday +%Y%m%d)
for daily backups.
I want to add up an important command too which most of us do face regularly:
Writing an archive in a different directory
You may also want to write an archive lto a different directory, like this:
tar czvf /tmp/mydirectory.tgz .
tej@tej-desktop:~$ tar -czf – Music/ | wc -c
1358
tej@tej-desktop:~$ tar -cjf – Music/ | wc -c
1471
Why it is so. file tarred with j should be less in size????
Tar command always seemed confusing to me. Your writeup clears any mis understanding. Nice work.
dear Ramesh,
first of all i’d like to thank you very much for your excellent work. being a newbie to BSD/linux thegeekstuff is my #1 choice to have a look at when it comes to help, understanding, and how-to… =:-) thank you very much again.
but right now, i am a bit confused: in 1. Creating an archvie using tar command, Note #2, you wrote that you like to keep the ‘cvf’ option unchanged for easy remembering, and you prefer to add additional options at the end. but if so, shouldn’t it be ‘cvfz’ for compressed gzip’s, and ‘cvfj’ for compressed bzip2′s? i mean to have ‘cvf’ together as you wrote one sentence before? did i miss something? or is it a simple spelling mistake?
again, sorry if it’s a stupid question, but keep in mind i’m still very new to tar (and all the other non-MS stuff), let’s call it doubtful, uncertain and precarious.
No tar tutorial is complete without an example that does a cross-network copy.
This example uses GNU tar, with –numeric-owner and so can, as in this example, be used to copy an entire system onto a system with a blank disk drive that’s been put into another computer. The target system needs to have the new blank disk partitioned (fdisk, cfdisk, gparted, etc.), and filesystems created (mke2fs, etc.) and mounted (mount) in the appropriate places under /mnt/. It may be handy to boot the target system using a “live” Linux cd, usb key, etc.
If you are logged in, as root, on the target system, the one with the new drive, you use:
ssh sourcesystem.example.com ‘tar -C / –numeric-owner -czf – .’ | tar -C /mnt -xzpf -
If you are logged in, as root, on the source system, the one being copied, you use:
tar -C / –numeric-owner -czf – . | ssh targetsystem.example.com ‘tar -C /mnt -xzpf -’
Note that the above command, or any other sort of whole system backup and restore, should _not_ be used to “clone” a system because of the many little bits of supposed-to-be-unique data that a modern system contains. Use your package management system to “clone”.
Tar is common. But tar doesn’t generate fully POSIX-compliant archives. A better tool is “pax”. It’s also more reliable in reconstructing file access rights. (And it handles both, tar and cpio formats.)
@tej parkash: The compressed size depends on the content of your Folder.
with latest version of tar, the options z or j does not need to be specified for listing or extracting.
Thanks for the useful article. The one suggestion I’d make is that the code to estimate final archive file size isn’t very useful in real life. The example for estimating the final size of the archive actually creates the archive, (in memory at least) so the estimate will take almost as long as actually doing the command in the first place. For small file sets you really don’t care about the size of the final output. For larger file sets where you are likely to care, the time to get the estimate is prohibitive. However that example is a good demonstration of the power of combining command line utilities by piping data between them. Great job!
Nice explanation.
tar does not use regular expressions (or regexp). it uses globbing – please do not mix these terms
Thanks – I’m always forgetting how to run tar to create a .tar.gz
Really cool Tutorial.