Xargs

By default, xargs delimits input with a space (or newline) to produce a list of files to operate on.

Wherever the replacement string occurs in the command you ask xargs to execute, it will be replaced by an argument.

Although our examples have used simple text files for illustration, you will seldom want to use xargs with input like this.

However, when xargs builds the command, it will pass as many parameters at once as it possibly can.

You can also use the -L option of xargs to have it treat lines as arguments rather than the default of individual blank-delimited tokens.

The xargs command will not build arbitrarily long commands.

By default, xargs breaks the input at blanks, and each resulting token becomes a parameter.

By the way, if you want to preview the commands that xargs produces, add the option -p or -t.

If such an error occurs, use a pipe and the xargs utility.

We could use xargs instead, but we already saw problems with blanks in file names.

Use the xargs tool as a filter for making good use of output culled from the find command.

Next, awk reduces the output to the process ID, which you feed into xargs.

In Listing 19 we try using find with -exec rather than ls with xargs.

In Listing 17 we first copy text1 to "text 1" and then show some ways of using a list of file names containing blanks with xargs.

In Listing 13 we illustrate the use of both forms and add an explicit invocation of echo to our use of xargs.

Listing 16 shows one way you might pass a directory listing through xargs to a command such as grep.

Use xargs outside of find .

On the other hand, xargs is rarely used except with other utilities, most often find.

If you run find on such a batch of files and pass the list of results to xargs, the spaces in the file names cause errors

Using the find command with the -exec option or with xargs

Listing 15. Example of using of the xargs tool

Listing 14. Example of output from the xargs tool

Listing 13. Example of the classic use of the xargs tool