bug#16859: tty-setup-hook can run twice

bug#16859: tty-setup-hook can run twice

[Glenn Morris]

Package: emacs
Version: 24.3.50

Current trunk on GNU/Linux.
I don't know if this matters, but tty-setup-hook can run twice.

From an xterm:

export TERM=xterm
export COLORTERM=rxvt

cat <<EOF >| /tmp/.emacs
(add-hook 'tty-setup-hook (lambda () (message "hi")))
EOF

HOME=/tmp ./src/emacs -nw
C-h e
  -> hi [2 times]

This is because tty-run-terminal-initialization runs terminal-init-xterm,
which in this case calls tty-run-terminal-initialization again with type
"rxvt".

Since several of the other init functions in term/ run
tty-run-terminal-initialization, this could happen with other terminal
types as well.

bug#16859: tty-setup-hook can run twice

[Glenn Morris]

Possible solutions:

1) Let-bind tty-setup-hook to nil round all calls to
tty-run-terminal-initialization in term/*.el.

2) Move running of tty-setup-hook out of tty-run-terminal-initialization,
into tty-create-frame-with-faces and command-line.

bug#16859: tty-setup-hook can run twice

[Stefan Monnier]

> 1) Let-bind tty-setup-hook to nil round all calls to
> tty-run-terminal-initialization in term/*.el.

I don't like let-binding hooks (e.g. it doesn't work right when the hook
has both a global and a buffer-local value).

> 2) Move running of tty-setup-hook out of tty-run-terminal-initialization,
> into tty-create-frame-with-faces and command-line.

I haven't looked at it, but it sounds preferable, yes,


        Stefan

bug#16859: tty-setup-hook can run twice

[Glenn Morris]

Stefan Monnier wrote:

>> 1) Let-bind tty-setup-hook to nil round all calls to
>> tty-run-terminal-initialization in term/*.el.
>
> I don't like let-binding hooks (e.g. it doesn't work right when the hook
> has both a global and a buffer-local value).
>
>> 2) Move running of tty-setup-hook out of tty-run-terminal-initialization,
>> into tty-create-frame-with-faces and command-line.
>
> I haven't looked at it, but it sounds preferable, yes,

Or you can have option 3:

3) Add optional DO-NOT-RUN-HOOK (or the inverse) argument to
tty-run-terminal-initialization.


BTW, I also noticed that the hook runs when emacs --daemon is started,
which seems odd?

bug#16859: tty-setup-hook can run twice

[Stefan Monnier]

> 3) Add optional DO-NOT-RUN-HOOK (or the inverse) argument to
> tty-run-terminal-initialization.

I guess for backward compatibility's sake, adding a RUN-HOOK is a good idea.

> BTW, I also noticed that the hook runs when emacs --daemon is started,
> which seems odd?

Indeed, since we do

  (unless (or noninteractive
              initial-window-system)
    (tty-run-terminal-initialization (selected-frame)))

it would make sense to also prevent tty-run-terminal-initialization when
in daemon (tho I thought `noninteractive' would be set for daemon, but
maybe this is run late enough that `noninteractive' has already been
changed to nil by then).


        Stefan