How do I use xargs with find?

The find command often outputs filenames with spaces or special characters, which can cause issues. Use 'find . -print0 | xargs -0 command' to handle such filenames safely. For example: find . -name '*.log' -print0 | xargs -0 rm.

Can xargs execute commands in parallel?

Yes, use the -P option followed by the number of parallel processes. For example: find . -name '*.jpg' -print0 | xargs -0 -P 4 convert -resize 50%.

xargs Command

Q: What does the xargs command do in Linux?

The xargs command reads items from standard input, delimited by blanks (which can be protected with double or single quotes or a backslash) or newlines, and executes the command one or more times using these items as arguments.

The xargs command in Linux is a powerful utility that reads items from standard input, delimited by blanks (which can be protected with double or single quotes or a backslash) or newlines, and executes the command one or more times using these items as arguments. It's particularly useful for building and executing commands when the input comes from another command's output.

Syntax

xargs [options] [command [initial-arguments]]

Description

xargs is used to execute a command with arguments that are read from standard input. This is crucial because many commands do not accept input directly from a pipe (|) as arguments. xargs bridges this gap by converting standard input into arguments for a specified command.

Common uses include:

Executing commands on a list of files generated by another command (e.g., find)
Processing multiple items from a list in a loop-like fashion
Building complex command lines dynamically
Handling filenames with spaces or special characters safely

Common Options

Option	Description
`-0`, `--null`	Input items are terminated by a null character instead of by whitespace. Useful with `find -print0`.
`-n count`	Use at most `count` arguments per command line.
`-P max-procs`	Run at most `max-procs` processes at a time; default is 1.
`-I replace-str`	Replace occurrences of `replace-str` in the initial arguments with names read from standard input.
`-t`, `--no-run-if-empty`	Print the command and its arguments to standard error before executing it.
`-r`, `--no-run-if-empty`	If the standard input contains only blanks or no characters, do not run the command.

Examples

Delete files found by find

find . -name '*.tmp' -print0 | xargs -0 rm

Finds all files ending with '.tmp' and deletes them safely, even if filenames contain spaces.

Copy files to a new directory

ls *.txt | xargs -I {} cp {} /backup/texts/

Copies all '.txt' files to the '/backup/texts/' directory.

Execute command for each line of input

cat servers.txt | xargs -I {} ssh {}

Reads server names from 'servers.txt' and attempts to SSH into each one.

Process files in parallel

find . -name '*.png' -print0 | xargs -0 -P 4 convert -resize 50%

Resizes all '.png' images in parallel using 4 processes.

Combine multiple lines into a single command

echo "arg1\narg2\narg3" | xargs echo Combined arguments:

Outputs: Combined arguments: arg1 arg2 arg3