How to use xargs command in Linux

Xargs is a powerful command-line utility in Linux that is used to execute commands with the help of the standard input. It's an essential tool for processing the input from other commands, files, or pipes, and executing actions on those inputs. Xargs can be used in various situations where you need to perform actions such as creating, deleting, or modifying files, or executing any other command-line utility that requires input from the standard input.

One of the key benefits of using xargs is its ability to handle long lists of input and execute commands on multiple items at once. This makes it a time-saving tool that can simplify complex shell scripts and automate repetitive tasks. In this article, we will explore the basic usage of xargs and various examples that demonstrate its capabilities.

Let's dive into the details of using xargs in Linux.

Comman syntax

The basic syntax of the xargs command is as follows:

xargs [OPTION]... [COMMAND [ARGUMENT]]

where:

• OPTION represents various options that can be passed to xargs to modify its behavior. Some common options include -i, -I, -t, -n, and -p.
• COMMAND represents the command that xargs will execute for each input item.
• ARGUMENT represents the arguments that will be passed to the COMMAND.

It's important to note that xargs reads its input from the standard input and executes the specified COMMAND for each input item. By default, the input items are separated by white spaces, but this can be changed using the -d option. The output from the COMMAND is written to the standard output, unless redirected using > or >>.

Usage examples

Let's see a basic example of how xargs can be used to execute a command with input from the standard input. The following command will execute the ls command for each input item:

$ echo "file1 file2 file3" | xargs ls
file1
file2
file3

In the example above, xargs takes the input file1 file2 file3 from the standard input and passes each item as an argument to the ls command. This is a simple demonstration of how xargs can be used to process inputs and execute commands on them.

Executing commands on files: Xargs can be used to execute commands on a list of files. For example, the following command will delete all .txt files in the current directory:

ls *.txt | xargs rm

Passing options to the command: Xargs can also be used to pass options to the executed command. For example, the following command will list the contents of all .txt files in the current directory:

$ ls *.txt | xargs -I {} cat {}

In the example above, the -I {} option is used to specify a placeholder for each input item. The placeholder {} is then used in the cat command to specify the file name for each input item.

Executing commands with arguments: Xargs can also be used to execute commands with arguments. For example, the following command will list the contents of all .txt files in the current directory with line numbers:

$ ls *.txt | xargs -I {} cat -n {}

Modifying the input delimiter: Xargs can also be used to modify the input delimiter, which is by default a white space. For example, the following command will list the contents of all files in the current directory, separated by a comma:

$ ls | xargs -d, -I {} cat {}

Limiting the number of parallel executions: Xargs can be used to limit the number of parallel executions of the command using the -P option. For example, the following command will execute the ls command on 5 files at a time:

$ ls | xargs -P 5 -I {} ls {}

These are just a few examples of how xargs can be used to automate tasks and simplify complex shell scripts. With its ability to process inputs, execute commands, and pass options and arguments, xargs is a versatile and essential tool for any Linux user.

xargs with find

The find command and xargs command are often used together to perform operations on a set of files. The find command can be used to search for files that meet certain criteria, while xargs can be used to execute a command on the found files.

Here's an example of how xargs can be used with find to delete all .txt files in the current directory:

$ find . -name "*.txt" | xargs rm

In this example, find is used to search for all .txt files in the current directory and its subdirectories, and xargs is used to delete those files.

Here's another example of how xargs can be used with find to change the permissions of all .txt files in the current directory to 644:

$ find . -name "*.txt" | xargs chmod 644

In this example, find is used to search for all .txt files in the current directory and its subdirectories, and xargs is used to change the permissions of those files to 644.

These are just a few examples of how xargs and find can be used together to automate tasks and perform operations on a set of files. By combining the capabilities of find and xargs, you can create powerful shell scripts that can simplify complex file operations.

xargs with awk

The xargs and awk commands can be used together to perform complex data processing tasks in Linux. xargs can be used to pass a list of inputs to awk, which can then be used to manipulate and format the data.

Here's an example of how xargs can be used with awk to print the sum of all the numbers in a file:

$ cat numbers.txt | xargs | awk '{ sum += $1 } END { print sum }'

In this example, the cat command is used to display the contents of the numbers.txt file, which contains a list of numbers. The output of the cat command is then passed to xargs, which converts the input into a list of arguments. Finally, awk is used to sum the numbers and print the result.

Here's another example of how xargs can be used with awk to find the average of all the numbers in a file:

$ cat numbers.txt | xargs | awk '{ sum += $1; count++ } END { print sum/count }'

In this example, awk is used to sum the numbers and count the number of elements in the list. The result is then divided by the count to find the average.

These are just a few examples of how xargs and awk can be used together to perform complex data processing tasks. With its ability to pass inputs and manipulate data, awk is a powerful tool that can be used in conjunction with xargs to automate tasks and simplify shell scripts.

The cat, awk, and xargs commands can be used together to perform complex data processing tasks and automate repetitive tasks in Linux. By combining the capabilities of these commands, you can create powerful shell scripts that can simplify complex data processing tasks.

Here's an example of how you can use cat, awk, and xargs to extract a column from a file, and then use that column as an argument to run another command:

$ cat file.txt | awk '{print $2}' | xargs -I {} command -arg1 {}

In this example, the cat command is used to display the contents of the file.txt file. The output of the cat command is then passed to awk, which is used to extract the second column of the file. The extracted column is then passed to xargs, which is used to run the command with arg1 set to the extracted column.

This is just one example of how cat, awk, and xargs can be used together to automate tasks and simplify complex data processing. By combining the capabilities of these commands, you can create powerful shell scripts that can streamline repetitive tasks and make your work more efficient.

Conclusion

In conclusion, the xargs command is a versatile tool in the Linux operating system that can be used to execute commands on a set of inputs. By combining xargs with other commands, such as find, awk, and cat, you can create powerful shell scripts that can automate repetitive tasks and simplify complex data processing. Whether you're working with large amounts of data or just need to streamline your workflow, xargs can help you get the job done more efficiently. With a little bit of practice, you'll be able to master the xargs command and use it to its full potential.