Questions and thoughts about input method protocol

Yichao Yu yyc1992 at
Fri Feb 1 05:39:08 PST 2013

On Fri, Feb 1, 2013 at 3:21 AM, Pekka Paalanen <ppaalanen at> wrote:
> On Thu, 31 Jan 2013 17:45:25 -0500
> Yichao Yu <yyc1992 at> wrote:
>> On Thu, Jan 31, 2013 at 5:19 PM, Pekka Vuorela <pvuorela at> wrote:
>> > Problem with window titles and all is that they are information not meant to
>> > input method. Those are meant for the user and can change any time and to
>> > anything. And using those will require application specific logic in the
>> > input method, like specific rules for specific application.
>> > Don't see that feasible except for very special cases.
>> They will never change to random things and the only necessary thing
>> to do is keyword matching. And it will able to work for most cases
>> unless you have a window title like "window 1".
> Hi Yu,
> I have a trivial example of an application that will always have a
> random window title: a terminal.
> The window titles of my terminals in X show the current working
> directory and some other environment variables. There is no way you can
> use the window title to infer anything useful, especially when it is a
> matter of user's shell and prompt preferences. It does not say
> "terminal" or "bash" anywhere. There is no keyword you could match.
> Also, other apps that run in the terminal, may or may not set the window
> title to their own random things.

You are right about the terminal, although that's not the most
important case for this: few people uses input method a lot in a

> Web browsers are actually the same. There is nothing requiring the
> browser name or website URL to be in the window title. You simply
> cannot trust it. In fact, in many cases on desktop, there can be an
> icon next to the title, and in that case it is just waste of space to
> have the application name in the window title.

Well, since what I mean is not what visually available to the user,
rather the title set in the protocol icon shouldn't matter, plus the
program name is also directly available (for the compositor) so the
program name is not what a  input method may need from the title(or
other context strings) but what's really inside if the application can
be used in different ways. It is indeed not 100% reliable, more on
this below.

> As you are now creating a new common protocol, you have a chance to
> design things to be reliable from the start. If you need more
> information from clients, add explicit protocol for it, and specify
> exactly what you want, and how it can be used.

Does what I mentioned in the previous email sound any better for you
(the three thing an input method will need that I can come up with
now)? Well what I really mean is the window title is really useful as
a fallback of the context string. It will indeed be better if the
application is willing to set a better one.

> Thanks,
> pq

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