bug#44824: 27.1; Org export as pdf and open file does not open it

[Maxim Nikulin <m.a.nikulin@gmail.com>]

On 31/01/2021 23:33, Eli Zaretskii wrote:
>>
>>>> To fix the problem it is better to use (make-process :connection-type
>>>> 'pipe ...) that unfortunately has no higher level wrappers.
>>>
>>> Wouldn't it work to let-bind process-connection-type to nil around the
>>> function that starts the async subprocess?

>> ...

> Well, I think we should try this, because if it works, it will show us
> a way to fix the problem.  (I don't see how lexical-binding could
> interfere with let-binding.)

It is not a great problem to use make-process:

https://lists.gnu.org/archive/html/emacs-orgmode/2021-01/msg00364.html

I think that at least a :sentinel should be added to improve error 
reporting. The code just before these lines has another problem (I hope 
it is really rare): 
https://lists.gnu.org/archive/html/emacs-orgmode/2021-01/msg00353.html

I would avoid shell since direct execution of the handler should be more 
robust, e.g. quoting of arguments is not necessary. Unfortunately RFC on 
mailcap states that command is executed by shell. On the other hand only 
a few of viewer entries have commands that could not be handled without 
shell.