Eli Zaretskii <eliz@gnu.org> writes:

>> (Is that even possible? Start a graphical frame from a tty Emacs?)
>
> Of course, it is.  emacsclient can do that.  Assuming Emacs was built
> with GUI support, of course.  We have this feature for several years
> now.
>

Indeed it can. Never tried it before, and kinda assumed it wouldn't
work. Silly me.

Anyways, I have a patch, below, that's my first stab at solving the
problem. All it does is call `check_x_display_info` with the current
frame and allows any resulting error signals to propagate back up.

Probably not the most elegant solution, but I'm not entirely clear what
can and can't be done from within the Emacs C core. Suggestions are very
welcome.

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