In some cases, it's necessary to print an output on stdout and save an output in a file. In general, command output can either be printed or can be saved in a file. To solve it, the tee command is used. This command reads from the standard input and writes to both standard output and files. The syntax of tee will be as follows:

tee [OPTION] [FILE …]

The tee command copies the output to each FILE and also to stdout. The OPTIONS can be as follows:

Writing an output to stdout and file: In general, to write an output to stdout and file, we will call the same command twice, with and without redirection. For example, the following command shows how to print an output on stdout and save it to a file:

$  ls /usr/bin/*.pl  # Prints output on stdout
/usr/bin/rsyslog-recover-qi.pl  /usr/bin/syncqt.pl
$  ls /usr/bin/*...