search for: openssh_hashknownhost

...the configuration of the ssh session being invoked, but some commands might alter their behavior based on the ssh configuration. My proposal is for ssh to export its current configuration to the environment established for the invoked subcommand. So the child process could (for example) examine ${OpenSSH_hashknownhosts} to decide how to update a known_hosts file. This is similarly useful to sshd's -C and -T options (though the mechanism is different, of course) -- so aligned tools don't need to re-implement (or track) OpenSSH's config file parsing code. One way to approach this would be to allow so...