ar command in Linux with examples
Last Updated : 11 Sep, 2024
The ‘ar’ command in Linux is a versatile tool used for creating, modifying, and extracting files from archives. An archive is essentially a collection of files bundled together in a specific structure, making it easy to manage multiple files as a single entity. Each file within the archive is referred to as a member of the archive. The ‘ar’ command is commonly used for creating static libraries, which are crucial in software development for linking compiled code into executable programs.
Syntax
ar [OPTIONS] archive_name member_files
Here, OPTIONS are flags that define the action you want to perform, ‘archive_name‘ is the name of the archive file you want to create or modify, and ‘member_files‘ are the individual files you wish to include in the archive.
Key Options for the ‘ar’ Command
Below are the most commonly used options with the ‘ar’ command, along with examples to demonstrate their use:
1. r (Insert Files into Archive)
This is used to create archive, insert files in archive. This is different from q as it deletes any previously existing members. If any member filename does not exist it throws an error. By default, it adds a new member at end of the file.
Example: Assume there is a file named star1 and you want to create archive named “super” without modifier then you can use the following command:
ar r super.a *star1
This will create an archive with member ‘star1′. With modifier it looks like as:
ar rv super.a *star1.txt
Note: The modifier ‘v’ gives a line or output with letter ‘a’ or ‘r’ indicating if the file is appended or not.
2. d (Delete Files from Archive)
Deletes modules from archive. Specify names of the modules as member…; When you add modifier ‘v’, ar lists each module as it is deleted.
ar d super.a star1.txt
In our previous case, we used ‘star1.txt’ in archive ‘super.a’, now we will delete that file from there.
In that we had ‘super.a’ archive storing ‘star1.txt’, after using ‘d’ without modifier it just deleted the file now lets see the same example with modifier ‘v’.
ar dv super.a star1.txt
With using modifier ‘v’ it listed module as they are deleted.
3. p (Print Archive Members)
This option is used to print the specified members of a archive in a standard output file if you do not use modifier it will print member as it is an output file whereas if you use modifier v then it will show member name before it is copied to output file.
ar p super.a
Here it gave the output which was written in our files stat1.txt and star2.txt, now let us check what happens when we use modifier v in it.
ar pv super.a
With the use of the modifier, first get the file name and then content written inside it.
4. t (List Archive Contents)
It displays the contents of the archive in a listed manner, usually, it shows the contents of the archive but if we use modifier O then it also shows the corresponding offset of each member.
ar t super.a (taking our old files and examples)
Here ‘t’ displayed the members of the archive, now lets see what it shows when we use modifier.
ar tO super.a
This time with the use of modifier we get the corresponding offset of each member.
5. x (Extract Archive Members)
It extracts each named member from the archive if you do not name the member to be extracted it extracts the whole archive. We can use ‘v’ modifier to list name of each member which is extracted. 
The modifier ‘v’ displays each file which is extracted and also we did not specify a name so it extracted the whole archive if we specify names of the member it extracts only that member. This command does not extract thin files as in our case, it just displays that it has extracted the archive. 
The above image shows extraction based on specified member name, and ‘v’ modifier lists file is extract.
Conclusion
The ‘ar‘ command is a useful tool in Linux for handling archives, especially for developers who create and manage static libraries. It offers various options to create, change, and extract files from archives, giving you complete control over what’s inside. Learning how to use the ar command can make managing files on Linux much easier and more efficient.