tar Command in Linux with Examples

The tar command in Linux, which stands for ‘tape archive’, is an essential command for creating and managing archives. It was originally designed for use with tape drives but is now widely used for different purposes, such as making tar backups, sharing files, and compressing data. In this article, we will explore how to use the ‘tar’ command in Linux, including its basic functions, and provide practical examples.

Table of Contents:

• Syntax of ‘tar’ command in Linux
• Tar Command Usage and Options
• What is an Archive file?
• Tar Command Examples
• Creating Tar Archives in Linux
• Generating an Uncompressed Archive
• Extracting Files and Directories in Linux
• Listing and Verifying Archives in Linux
• Appending Files to an Archive
• Updating Files in an Archive
• Concatenating Multiple Tar Files in Linux
• Estimating Archive Size
• Using Wildcards with the Tar Command
• Summary

 tar [options] [archive-name] [file/directory...]

Example 1: Creating a Tar Archive

To initiate the archiving process with the ‘tar’ command, you can use the following syntax:

tar -c[f|j|z] [archive-name] [file/directory...]

• The ‘-c‘ flag instructs ‘tar’ to create a new archive.
• ‘[f|j|z]‘ indicates the compression method: ‘f’ for no compression, ‘j’ for bzip2 compression, and ‘z’ for gzip compression.
• ‘[archive-name]‘ specifies the name of the resulting archive file.
• ‘[file/directory…]‘ lists the files or directories you want to include in the archive.

Example:
For instance, to create a compressed archive named ‘myarchive.tar.gz’ from the ‘myfolder’ directory, you can use:

tar -czf myarchive.tar.gz myfolder

Example 2: Creating an Uncompressed Archive using tar Command

Syntax for Creating an Uncompressed Archive:

You can also create an uncompressed archive with the ‘tar’ command. Here’s how:

$ tar cvf archive_name.tar dirname/

• ‘c’: To create a new archive.
• ‘v’ (optional): To verbosely list files being processed.
• ‘f’: To specify the archive file name.

Example:
This command creates ‘archive_name.tar’ from all the files in the ‘dirname/’ directory. Alternatively, you can specify individual files:

$ tar cvf archive_name.tar abc def

Example 3: Creating a Compressed Archive using tar Command

(i) gzipped tar:

To create a gzip-compressed tar archive, use the ‘z’ option like this:

$ tar cvzf archive_name.tar.gz dirname/

Note: ‘.tgz’ is the same as ‘.tar.gz’. Do not use a hyphen (-) before the options for this to work properly.

(ii) bzipped tar:

For a bzip2-compressed tar archive, use the ‘z’ option as follows:

$ tar cvfj archive_name.tar.bz2 dirname/

Note: ‘.tbz’ and ‘.tb2’ are the same as ‘.tar.bz2’. Please remember that bzip2 compression takes more time to compress and decompress compared to gzip. However, bzip2 archives have smaller sizes.

Example 4: Extracting Files from an Archive

To extract files from an archive, use the ‘x’ option followed by the ‘f’ option to specify the archive file. For instance, to extract the contents of “archive_name.tar” into the current directory, you would use:

$ tar xvf archive_name.tar

Example 5: Extracting a compressed tar archive

(i) Extracting a gzipped tar:

To open a compressed tar file created with gzip, use this command:

$ tar xvfz archive_name.tar.gz

(ii) Extracting a bzipped tar:

For a compressed tar file created with bzip2, use this command:

$ tar xvfj archive_name.tar.bz2

Example 6: Listing an uncompressed archive using the tar command

Before extracting, you can view the content of a *.tar file with this command:

$ tar tvf archive_name.tar

Example 7: Listing a compressed archive using the tar command

(i) Listing a gzipped tar:

To list the contents of a gzip-compressed tar archive, use the ‘z’ option:

$ tar tvfz archive_name.tar.gz

(ii) Listing a bzipped tar:

For a bzip2-compressed tar archive, use the ‘j’ option:

$ tar tvfj archive_name.tar.bz2

Note: If there are lots of files in the archive, you can use a “less” command to read through the list.

Example 8: Extract a single file from tar, tar.gz, tar.bz2 file

To extract a specific file from a tar archive, include the file name at the end of the ‘tar xvf’ command:

$ tar xvf archive_file.tar /path/file

Use the ‘z’ or ‘j’ option as per the compression method (gzip or bzip2):

$ tar xvfz archive_file.tar.gz /path/file

OR

$ tar xvfj archive_file.tar.bz2 /path/file

Note: When dealing with multiple files sharing the same extension, you can use the wildcard option:

$ tar xvf archive_file.tar --wildcards '*.c'

Example 9: Extract directory from tar, tar.gz, tar.bz2 file

To extract a directory from a tar archive, add the directory name at the end of the ‘tar xvf’ command like this:

$ tar xvf archive_file.tar /path/dir/

If you need to extract multiple directories from the archive, specify each directory individually at the end:

$ tar xvf archive_file.tar /path/dir1/ /path/dir2/

Make sure to use the ‘z’ or ‘j’ option based on whether the file is gzip or bzip2 compressed.

Example 10: Appending Files to an Archive

To add a file or directory to an existing archive, you can use the ‘-r’ option:

$ tar rvf archive.tar abc

This command appends the file ‘abc’ to ‘archive.tar’. Adding a directory follows a similar approach:

$ tar rvf archive.tar dir/

Note: You cannot add files or directories to a compressed archive. Attempting to do so will result in a “tar: Cannot update compressed archives” error.

Example 11: Updating Files in an Archive

The -u option allows you to update files in an archive. If a file with the same name already exists in the archive, it will be replaced. For example, to update “existingfile.txt” in “myarchive.tar,” use:

tar uf myarchive.tar existingfile.txt

Example 12: Concatenating Multiple Tar Files in Linux

You can concatenate multiple archives into one using the -A option. For example, to concatenate “archive1.tar” and “archive2.tar” into a new archive called “merged.tar,” use:

tar -Af merged.tar archive1.tar archive2.tar

Example 13: Estimate the tar archive size

To estimate the size of a tar file in kilobytes (KB) before creating it, you can use the following command:

$ tar -cf - /directory/to/archive/ | wc -c

This command calculates the size of the tar file (in bytes) by piping the result of the ‘tar’ command to the ‘wc’ command, which counts the bytes.

Again, make sure to use the ‘z’ or ‘j’ option depending on whether you intend to use gzip or bzip2 compression.