Command-line construction of auguments list with xargs

xargs is a really useful unix command line tool that can be used to construct an argument list for piping into other unix commands.
For example, lets say we want to find and delete all files fitting a certain criteria, such as those with a suffix of “.java~”.
We can use the find utility to easily list these:


$ find . -name *.java~
./path/to/file/file1.java~
./path/to/file/file2.java~
./path/to/file/file3.java~
./path/to/file/file4.java~


However, the output from this is in the form of a list, which cannot be piped directly into a command like rm. If the list is very long, it can be difficult to write it out manually into a singe argument list.

Instead, we can pass the output from the find command into xargs to convert this list into a single argument list for us:


$ find . -name *.java~ | xargs
./path/to/file/file1.java~ ./path/to/file/file2.java~ ./path/to/file/file3.java~ ./path/to/file/file4.java~


This can then be piped into rm or any other command as needed.

This is just one simple example of the use of xargs. It’s a much more powerful tool that is able to handle much larger argument lists with great flexibility.