Ssh Zfs Cat (bad magic number)
Problem
ssh remote zfs send zroot/some@snap | zfs receive fails with
cannot receive: invalid stream (bad magic number)
Solution
The solution is to use the real ssh executable instead: /usr/bin/ssh ….
Explanation
The invoked ssh is not the ssh binary you expect.
To illustrate further, try ssh cat somefile > /tmp/somefile and you will see
that the resulting local file is different than the original file.
Similarly to this person on StackOverflow,
I had an ssh() function defined in my .zshrc to update the terminal title
with escape characters. Something like print -nR $'\033k'$title$'\033'\\.