Re: [TCLCORE] Advice requested regarding [send] on macOS

[Marc C. <cul...@gm...>]

Erik,

I now think that much of what I said about the consequences of having a
unique NSApplication object is wrong.  I think there is actually no
obstacle to implementing a send command on macOS which can send commands to
interpreters in a different Wish process.  The only problem is that no one
ever wrote such an implementation.

- Marc

On Sat, Aug 16, 2025 at 7:17 AM Marc Culler <cul...@gm...> wrote:

> Apple does provide IPC mechanisms.  I don't know whether they would be
> suitable, but I am pretty sure they would.  However, the current
> implementation of [send] does not attempt to use them.  If you look at the
> top of macosx/TkMacOSXSend.c you will see this very old comment (note that
> "gestalts" no longer exist in macOS):
>
>  *      This file provides procedures that implement the "send" command,
>  *      allowing commands to be passed from interpreter to interpreter.
> This
>  *      current implementation for the Mac has most functionality stubbed
> out.
>  *
>  *      The current plan, which we have not had time to implement, is for
> the
>  *      first Wish app to create a gestalt of type 'WIsH'. This gestalt
> will
>  *      point to a table, in system memory, of Tk apps. Each Tk app, when
> it
>  *      starts up, will register their name, and process ID, in this table.
>  *      This will allow us to implement "tk appname".
>  *
>  *      Then the send command will look up the process id of the target
> app in
>  *      this table, and send an AppleEvent to that process. The AppleEvent
>  *      handler is much like the do script handler, except that you have to
>  *      specify the name of the tk app as well, since there may be many
>  *      interps in one wish app, and you need to send it to the right one.
>  *
>  *      Implementing this has been on our list of things to do, but what
> with
>  *      the demise of Tcl at Sun, and the lack of resources at Scriptics it
>  *      may not get done for awhile. So this sketch is offered for the
> brave
>  *      to attempt if they need the functionality...
>
> - Marc
>
>
> On Sat, Aug 16, 2025 at 1:17 AM Donal Fellows <
> don...@ma...> wrote:
>
>> I would be very startled if it *isn't* the exact same issue, a
>> combination of needing a suitable IPC mechanism for doing the discovery and
>> communications, and system policy restricting access to such things even if
>> they exist.
>>
>> Donal.
>>
>> ------------------------------
>> *From:* Erik Leunissen via Tcl-Core <tcl...@li...>
>> *Sent:* Saturday, August 16, 2025 07:12
>> *To:* Marc Culler <cul...@gm...>
>> *Cc:* tcl...@li... <tcl...@li...>
>> *Subject:* Re: [TCLCORE] Advice requested regarding [send] on macOS
>>
>> Related to this matter: I noticed (in a debug statement issued by me for
>> execution at Github) that
>> interpreters in another process are not returned by [winfo interps] on
>> macOS. (See the script below
>> to verify that). I'm suspecting that this is for the
>> very same reason/cause. Can you please give your view about that
>> (confirm/deny if
>> possible) ?
>>
>>