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I want to use async-shell-command to run a .bat file on Windows.
Reading the function documentation it says:

(defun async-shell-command (command &optional output-buffer error-buffer)
  "Execute string COMMAND asynchronously in background.
...
To run COMMAND without displaying the output
in a window you can configure `display-buffer-alist' to use the action
`display-buffer-no-window' for the buffer `*Async Shell Command*'.

Where I mark in bold what I want to achieve: run COMMAND without displaying the output.

So, I guess I need to configure display-buffer-alist variable to use display-buffer-no-window action for *Async Shell Command* buffer. It seems simple...

Checking the display-buffer-alist documentation:

(defcustom display-buffer-alist nil
  "Alist of conditional actions for `display-buffer'.
This is a list of elements (CONDITION . ACTION), where:

 CONDITION is either a regexp matching buffer names, or a
  function that takes two arguments - a buffer name and the
  ACTION argument of `display-buffer' - and returns a boolean.

 ACTION is a cons cell (FUNCTION . ALIST), where FUNCTION is a
  function or a list of functions.  Each such function should
  accept two arguments: a buffer to display and an alist of the
  same form as ALIST.  See `display-buffer' for details.

Well... this is where my head starts to get lost on Emacs/Elisp ecosystem.
Should I do something like this (where I do not know what to put on ???):

(add-to-list 'display-buffer-alist '("*Async Shell Command*" . (display-buffer-no-window . ???)) )

Any help/hints will be appreciated.

nephewtom
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2 Answers2

5

Try this:

(add-to-list 'display-buffer-alist '("*Async Shell Command*" display-buffer-no-window (nil)))

The buffer is still created and it still gets the output of the command (or the error output): it is just not displayed automatically, but you can still get to it to look at what happened with the usual buffer selection mechanisms (C-x b etc).

NickD
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  • Thanks for answering. I haven't tested that one, but just replacing ??? with nil works for me. – nephewtom May 07 '20 at 15:36
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    It does not make much difference in this case: the dotted-pair syntax `(a . (b . nil)` is equivalent to the list syntax `(a b)`, so you have no placeholder for the "action alist" alluded to in the doc string of `display-buffer-alist`. The list syntax I used does have such a placeholder and explicitly says that the action alist is empty. In general, it is easier to read list syntax rather than dotted-pair syntax, so if there is a choice you probably want to go with list syntax. – NickD May 07 '20 at 16:22
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Basically I added a nil, instead ??? to my question, and it is working: 

(add-to-list 'display-buffer-alist '("*Async Shell Command*" . (display-buffer-no-window . nil)) )
nephewtom
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