Alternative to the tee command without STDOUT

Another option that avoids piping the stuff back and then to /dev/zero is

sudo command | sudo dd of=FILENAME

The dd solution still prints junk to stderr:

$ ls | sudo dd of=FILENAME
0+1 records in
0+1 records out
459 bytes (459 B) copied, 8.2492e-05 s, 5.6 MB/s

That can be avoided using the status option:

command | sudo dd status=none of=FILENAME

Another interesting possibility (for Linux anyway):

command | sudo cp /dev/stdin FILENAME

To copy TTY input into a file, I often do this:

sudo cp /dev/tty FILENAME

It's too bad tee doesn't have an option to suppress stdout.

You could use a script. I.e. put something like this in i.e. $HOME/bin/stee, 0tee or similar:

#!/bin/bash

argv=
while [[ "$1" =~ ^- ]]; do
    argv+=" $1"
    shift
done

sudo tee $argv "$1" > /dev/null

#!/bin/bash

sudo tee "$@" > /dev/null

Make it executeable:

$ chmod 755 stee

Now do i.e.:

$ ls -la | stee -a /root/foo