Playing with xargs

Unix commands accept data either from the standard input (stdin) or as command line arguments. Previous examples have shown how to pass data from one application's standard output to another's standard input with a pipe.

We can invoke applications that accept command-line arguments in other ways. The simplest is to use the back-tic symbol to run a command and use its output as a command line:

$ gcc `find '*.c'`

This solution works fine in many situations, but if there are a lot of files to be processed, you'll see the dreaded Argument list too long error message. The xargs program solves this problem.

The xargs command reads a list of arguments from stdin and executes a command using these arguments in the command line. The xargs command can also convert any one-line or multiple-line text inputs into other formats, such as multiple lines (specified number of columns) or a single line, and vice versa.

Getting ready

The xargs command should be the first command to appear after...