“Unix pipes and redirection are as useful as your text
editor or a shell script. In Part 2 of this series, Mo Budlong
explores some of the more advanced features of pipes and
redirection….“
“Combining standard output and standard error Redirection is
frequently used for jobs that run for a long period of time, or for
jobs that produce a lot of output. For such jobs, redirection can
capture the results in a file. When this is done, it’s also
necessary to capture any output errors. Remember that if you
redirect standard output but not standard error, output will go to
a file and error messages will still go to your screen. The
following find command will save the results to found.txt, although
errors still appear on the screen.”
$ find / -name *.txt -exec ls -l {} ; >found.txt
find: /some/directory: Permission denied
find: /another/one: Permission denied
$