bug#646: emacsclient with no args to behave like -a

[Jim Porter <jporterbugs@gmail.com>]

On 8/26/2021 8:31 PM, Lars Ingebrigtsen wrote:
> "J. Pablo "Fernández\"" <pupeno@pupeno.com> writes:
> 
>> It would be nice if emacsclient, when called with no arguments, would
>> just run the alternate editor. I've configured emacs as my alternate
>> editor so emacsclient for me is basically a "open this in an existing
>> emacs or run one otherwise", the only problem for that to work
>> completely is having it working with no arguments.
> 
> (I'm going through old bug reports that unfortunately weren't
> resolved at the time.)
> 
> It seems like this has been fixed in the 13 years since it was reported.
> 
> I did:
> 
> larsi@elva:~/src/emacs/trunk$ export ALTERNATE_EDITOR=nano
> larsi@elva:~/src/emacs/trunk$ ./lib-src/emacsclient /tmp/foo
> 
> and that opened nano.

It sounds to me like the "args" in question would be "/tmp/foo" in this 
case. On Emacs 27.2 and 28.0.50, I see:

   $ export ALTERNATE_EDITOR=nano
   $ lib-src/emacsclient
   lib-src/emacsclient: file name or argument required
   Try 'lib-src/emacsclient --help' for more information

 From my reading, this is the original reporter's preferred behavior:

   1) If Emacs is not currently running
      a) `emacsclient file.txt' starts Emacs and opens file.txt
      b) `emacsclient' starts Emacs (as though running `emacs')
   2) If Emacs is currently running
      a) `emacsclient file.txt' opens file.txt in the existing Emacs session
      b) `emacsclient' brings some frame in the existing Emacs session 
to the foreground