On Sat, Oct 14, 2023 at 07:07:57AM +0200, to...@tuxteam.de wrote:
> On Fri, Oct 13, 2023 at 01:06:20PM -0700, Van Snyder wrote:
> > I haven't figured out how to unlock the XTerm after accidentally giving
> > it Alt-Shift-P.
I'm not seeing whatever it is you're seeing here. On Debian 12, if I
launch an xterm (simply "xterm &") with bash running inside it, and
press Alt-P I get this character: ð
Shift-Alt-P gives me this character: Ð
This is independent of whether bash is in emacs mode or vi mode.
> > But I did work out how to prevent it. Put
> > xterm*altIsNotMeta: truexterm*altSendsEscape: true
> > in your .Xdefaults (or .Xresources, or link those files together), then
> > xrdb -merge ~/.Xdefaults
>
> Interesting. If I do that I see a colon, which disappears if I
> hit enter afterwards. Then things are "back to normal".
>
> If I run "od -C" on that term, I see the sequence "1b P", so I
> guess the term is just passing "ESC P" to the shell, and the one
> doing the magic is actually the shell running in there.
>
> The behaviour is the same if I do "ESC P". Does that "hang your
> Xterm", too?
Looks like your bash is in emacs (default) mode. Pressing Esc P in
emacs mode triggers this guy:
"\eP": do-lowercase-version
whose description in readline(3readline) says
do-lowercase-version (M-A, M-B, M-x, ...)
If the metafied character x is uppercase, run the command that
is bound to the corresponding metafied lowercase character. The
behavior is undefined if x is already lowercase.
So... apparently it's supposed to act the same as "metafied lowercase p",
which I guess means it's running this guy:
"\ep": non-incremental-reverse-search-history
non-incremental-reverse-search-history (M-p)
Search backward through the history starting at the current line
using a non-incremental search for a string supplied by the
user.
I'm not 100% sure what that means, but maybe you can figure it out if
you continue experimenting with it. I don't normally run bash in emacs
mode myself, so many of these readline features are foreign to me.
Anyway, all of that's an interesting tangent, but I still don't get
a "freeze" in xterm from any of this.
Van Snyder, can you try running this in your xterm:
bind -p | grep P
That should tell us whether you have any unusual readline bindings
involving the letter P (capital) which might be at fault here. In my
shell, I just have these:
unicorn:~$ set -o vi
unicorn:~$ bind -p | grep P
"P": self-insert
unicorn:~$ set -o emacs
unicorn:~$ bind -p | grep P
"\C-xP": do-lowercase-version
"\eP": do-lowercase-version
"P": self-insert
If yours is different, then we have something to investigate.
