changing comint-input-ring-file-name in process in shell

changing comint-input-ring-file-name in process in shell

[Seb]

Hi,

A program that runs in shell mode uses a local history file.  Therefore,
I'd like to set `comint-input-ring-file-name' to that file.  I use the
program by doing "M-x shell", and then start the program in the shell
buffer by typing its name and hitting ENTER.  The program's prompt
replaces the shell's at this point.  I thought that subsequently
evaluating the following in the shell buffer would allow me to cycle
through the local history file:

(setq comint-input-ring-file-name
      "/path/to/local/.bash_history"))

However, cycling with "M-p" or "M-n" cycles the input through the
initial `comint-input-ring-file-name' set by the shell buffer, in my
case ~/.bash_history since I'm using bash.  Doing "C-h v
comint-input-ring-file-name" does show the new value
("/path/to/loca/.bash_history"), so I don't understand what is going
on.  Any help would be appreciated.

Cheers,

-- 
Seb

Re: changing comint-input-ring-file-name in process in shell

[Kevin Rodgers]

Seb wrote:
> Hi,
> 
> A program that runs in shell mode uses a local history file.  Therefore,
> I'd like to set `comint-input-ring-file-name' to that file.  I use the
> program by doing "M-x shell", and then start the program in the shell
> buffer by typing its name and hitting ENTER.  The program's prompt
> replaces the shell's at this point.  I thought that subsequently
> evaluating the following in the shell buffer would allow me to cycle
> through the local history file:
> 
> (setq comint-input-ring-file-name
>       "/path/to/local/.bash_history"))
> 
> However, cycling with "M-p" or "M-n" cycles the input through the
> initial `comint-input-ring-file-name' set by the shell buffer, in my
> case ~/.bash_history since I'm using bash.  Doing "C-h v
> comint-input-ring-file-name" does show the new value
> ("/path/to/loca/.bash_history"), so I don't understand what is going
> on.  Any help would be appreciated.

The file is read once by shell-mode (not comint-mode), when you execute
`M-x shell'.  That is why the doc string for comint-input-ring-file-name
says "This variable is buffer-local, and is a good thing to set in mode hooks."

How about:

(let ((comint-input-ring-file-name "/path/to/local/.bash_history"))
   (shell))

-- 
Kevin Rodgers
Denver, Colorado, USA

Re: changing comint-input-ring-file-name in process in shell

[Seb]

On Sat, 07 Nov 2009 00:10:28 -0700,
Kevin Rodgers <kevin.d.rodgers@gmail.com> wrote:

[...]

> How about:

> (let ((comint-input-ring-file-name "/path/to/local/.bash_history"))
> (shell))

Thanks for the explanation Kevin.  There is no difference with your
suggestion, however.  In the resulting shell buffer I see:

,-----[ C-h v comint-input-ring-file-name RET ]
| comint-input-ring-file-name's value is "~/.bash_history"
| Local in buffer *shell*; global value is nil
| 
| Documentation:
| If non-nil, name of the file to read/write input history.
| See also `comint-read-input-ring' and `comint-write-input-ring'.
| 
| This variable is buffer-local, and is a good thing to set in mode hooks.
| 
| You can customize this variable.
| 
| [back]
`-----

and cycling shows that: i.e. "M-n" and "M-p" cycle through
~/bash_history, rather than the value in the `let' statement.  This is
strange.  This is on Emacs 23.


-- 
Seb

Re: changing comint-input-ring-file-name in process in shell

[Seb]

On Sat, 07 Nov 2009 15:44:09 -0600,
Seb <spluque@gmail.com> wrote:

> On Sat, 07 Nov 2009 00:10:28 -0700,
> Kevin Rodgers <kevin.d.rodgers@gmail.com> wrote:

[...]

>> How about:

>> (let ((comint-input-ring-file-name "/path/to/local/.bash_history"))
>> (shell))

> Thanks for the explanation Kevin.  There is no difference with your
> suggestion, however.  In the resulting shell buffer I see:

> ,-----[ C-h v comint-input-ring-file-name RET ]
>> comint-input-ring-file-name's value is "~/.bash_history" Local in
>> buffer *shell*; global value is nil
>> 
>> Documentation: If non-nil, name of the file to read/write input
>> history.  See also `comint-read-input-ring' and
>> `comint-write-input-ring'.
>> 
>> This variable is buffer-local, and is a good thing to set in mode
>> hooks.
>> 
>> You can customize this variable.
>> 
>> [back]
> `-----

> and cycling shows that: i.e. "M-n" and "M-p" cycle through
> ~/bash_history, rather than the value in the `let' statement.  This is
> strange.  This is on Emacs 23.

I eventually solved this with:

(defun grass (full-location)
  "Call grass with FULL-LOCATION arguments and set up a shell buffer
to work on. FULL-LOCATION must be a fully-qualified GRASS location;
i.e. it must include GISDBASE/LOCATION_NAME/MAPSET.

The GRASS process runs in a shell buffer, named *GRASS*."
  (interactive "DLocation: ")
  (let ((grassbuf "*GRASS*"))
    (shell grassbuf)
    (comint-send-string grassbuf (concat "grass " full-location "\n"))
    (setq comint-input-ring-file-name
	  (or (getenv "HISTFILE")
	      (concat (directory-file-name full-location)
		      "/.bash_history")))
    (comint-read-input-ring)))

Cc'ing the grass-user list where it might be of interest.

Thanks,

-- 
Seb

Re: changing comint-input-ring-file-name in process in shell

[Kevin Rodgers]

Seb wrote:
> On Sat, 07 Nov 2009 00:10:28 -0700,
> Kevin Rodgers <kevin.d.rodgers@gmail.com> wrote:
> 
> [...]
> 
>> How about:
> 
>> (let ((comint-input-ring-file-name "/path/to/local/.bash_history"))
>> (shell))
> 
> Thanks for the explanation Kevin.  There is no difference with your
> suggestion, however.  In the resulting shell buffer I see:
> 
> ,-----[ C-h v comint-input-ring-file-name RET ]
> | comint-input-ring-file-name's value is "~/.bash_history"
> | Local in buffer *shell*; global value is nil
> | 
> | Documentation:
> | If non-nil, name of the file to read/write input history.
> | See also `comint-read-input-ring' and `comint-write-input-ring'.
> | 
> | This variable is buffer-local, and is a good thing to set in mode hooks.
> | 
> | You can customize this variable.
> | 
> | [back]
> `-----
> 
> and cycling shows that: i.e. "M-n" and "M-p" cycle through
> ~/bash_history, rather than the value in the `let' statement.  This is
> strange.  This is on Emacs 23.

How do you set comint-input-ring-file-name to "~/.bash_history"?

i.e. at the top-level or within shell-mode-hook?

If the latter, the hook will override the let binding.

-- 
Kevin Rodgers
Denver, Colorado, USA