The xargs command

The xargs command builds command lines from standard input.

xargs [options] [command [initial arguments]]

With no arguments, xargs will take strings from standard input, strip off the newlines, and echo them to standard output. However, if you specify a command, xargs will use the data from standard input as the arguments for the command.

Common options:

-t

Verbose output. Prints the command to standard error before executing it.

-p

Run the commands in interactive mode, prompting the user before running each command.

-i

Replace a string ({} by default) in the initial arguments with the strings read from standard input.

Examples:

• Strip all newlines from a file

  cat filenames | xargs

• Get a directory listing of all filenames that are in a file:

  xargs -t ls -l < filenames

• Find the table tag in all html files:

  find . \( -name "*.html" -o -name "*.htm" \) | xargs grep -i "<table"

• Simple report of all socket files on the system:

  find / -type s | xargs -i echo {} is a socket

• Find all .c and .h files that include non-standard characters.

  find . -name "*.[ch]" | xargs grep -l "[^ -~\t]"

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