emacsclient –alternate-editor= “Could not start the Emacs daemon”; "standard input is not a tty"

[Matthew McClure <matt@continuousdelta.com>]

How might I tell emacsclient that it shouldn't need a tty to start the
Emacs daemon?

I'm using Emacs 26.2 from Homebrew Cask.

I have a Keyboard Maestro macro intended to create a new Emacs frame.

/usr/local/bin/emacsclient -n -c --alternate-editor=

It works in Bash in Terminal. If an Emacs server isn't already
running, the `--alternate-editor=` argument says to start the server
and try again.

In Keyboard Maestro, it works if an Emacs server is already running.
Otherwise, Keyboard Maestro shows the following message.

/usr/local/bin/emacsclient: can't find socket; have you started the server?
To start the server in Emacs, type "M-x server-start".
emacs: standard input is not a tty
Error: Could not start the Emacs daemon

I'm surprised that emacsclient tries to start the daemon in a way that
requires a tty.

How might I tell emacsclient that it shouldn't need a tty to start the
Emacs daemon?

-- 
Matthew McClure
Continuous Delta
https://www.continuousdelta.com/