tee ist ein Identitätsfilter, er kann das Ergebnis in stdout ausgeben und speichern:
tee
Redirect output to multiple files, copies standard input to standard
output and also to any files given as arguments. This is useful when you
want not only to send some data down a pipe, but also to save a copy.
Syntax
tee [options]... [file]...
Options
-a
--append
Append standard input to the given files rather than overwriting
them.
-i
--ignore-interrupts'
Ignore interrupt signals.
Example:
ps -ax | tee processes.txt | more
If a file being written to does not already exist, it is created.
If a file being written to already exists, the data it previously
contained is overwritten unless the `-a' option is used.