bug#24949: Command-line argument parsing: named daemons

[Glenn Morris <rgm@gnu.org>]

Package: emacs
Severity: minor
Version: 25.1

This starts a daemon with a server named "FOO":
   emacs -Q --daemon=FOO

(This usage is documented in the "Initial Options" appendix of the
manual, but not mentioned in --help, or the man page.)


But this very similar form does not work (it starts an un-named daemon and
visits file "FOO"):
   emacs -Q --daemon FOO

Compare with something like "--chdir /tmp", where both forms (with and
without "=") work.

This is due to the fragility of the Emacs argument parsing code,
which seems pretty home-grown. In particular, I guess it is because
struct standard_args has --daemon listed as taking no arguments.
Options with optional arguments don't seem to be handled.

There is a 20-year old comment in emacs.c:

   Too bad we can't just use getopt for all of this, but we don't have
   enough information to do it right.

Perhaps standard argument parsing libraries have improved since then...?