xargs Notes

Useful Options

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#-n max-args, --max-args=max-args
#  Use  at  most max-args arguments per command line.
find . | xargs -n1 echo

#-I replace-str
find . | xargs -n1 -I% echo % suffix

#-P max-procs, --max-procs=max-procs
#  Run up to max-procs processes at a time; the default is 1.
find . | xargs -P10 -n1 -I% sleep 1

#-0, --null
#  Input items are terminated by a null character instead of by whitespace.
find . -type f -name "*.java" -print0 |xargs -0 grep -li "keyword"

#-p, --interactive
#  Prompt the user about whether to run each command line and read a line from the terminal. Implies -t.
find . | xargs -p -n1 echo

#-t, --verbose
#  Print the command line on the standard error output before executing it.

#--delimiter=delim, -d delim
#  Input items are terminated by the specified character.

#-a file, --arg-file=file
#  Read items from file instead of standard input.

Tricks

Execute Shell Scripts

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# The word bash at the end of the line is interpreted by bash
# -c as special parameter $0.
# The single quote ' is critical, otherwise $filename will be
# replaced before the script is executed.
find /path -type f -name '*~' -print0 | xargs -0 bash -c \
'for filename; do cp -a "$filename" ~/backups; done' bash

Prevent xargs from Quitting on Error

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# instead echo the commands and pipe to bash, echo will not return error
find . | xargs -n1 echo command_that_might_exit | bash

Reference

xargs - Wikipedia
prevent xargs from quitting on error