pub fn no_master(host: &Host) -> ErrorExpand description
The missing-master error, with the socket directory prepared first.
ssh will not create the directory holding a control socket: it binds a
temporary name inside it and fails with
unix_listener: cannot bind to path ...: No such file or directory. Since
coop defaults socket to ~/.ssh/coop/<host>.sock and never created that
directory, the command coop printed could not work – and it failed after
the 2FA prompt, so the user paid a hardware-token tap to find out, and the
error read as a broken ssh config rather than a missing mkdir.
Done here rather than at config load so it is a consequence of asking for a
master, not a side effect of coop --help.