Introduction to Unix

4.8. tee

tee

Copy standard input to each FILE, and also to standard output.

SYNOPSIS

tee [-a] [FILE]…

OPTIONS

-a, --append

append to the given FILEs, do not overwrite

tee is useful for debugging complex pipeline commands and for achieving intermediate results.

EXAMPLE

$ who | tee who$(date +"%F-%T").txt | sort