Shell argument quoting woes

Shell argument quoting woes

[Thorsten Jolitz]

Hi List, 

assume this works in a shell

,------------------------
| $ prg -'fun "strg" num'
`------------------------

with 'prg' being a shell-command (for bash on GNU/Linux) calling a program,
'fun' being a function defined in that program, 'strg' being a string argument
to that function, and 'num' being a numeric argument to that function.

The task is to make a string out of this in an Elisp program and give
this 'cmd' as single argument to an Elisp function that then does
something like

#+begin_src emacs-lisp
(let ((cmdlist (split-string cmd)))
  (set-buffer (apply 'make-comint "buffer-name" (car cmdlist)
                     nil (cdr cmdlist) ) ))
#+end_src

Experimenting with (format "%s %S etc" ...) and (shell-quote-argument..) did
not result in anything that works. It seems the outcome is either

,--------------------
| prg -'fun strg num'
`--------------------

or

,------------------------
| prg -'fun \"strg\" num'
`------------------------

or

,--------------------------------
| prg\\ -\\'fun\\ \\\"strg\\\"\\ num\\'
`--------------------------------

or something similar, all resulting in errors.

Trying to replace the single quotes in that line with double-quote did not
work either.

How can I quote such a 'cmd' string in a way that it finally arrives as

,------------------------
| $ prg -'fun "strg" num'
`------------------------

?

-- 
cheers,
Thorsten

Re: Shell argument quoting woes

[Rustom Mody]

On Thursday, July 25, 2013 7:00:32 PM UTC+5:30, Thorsten Jolitz wrote:
Seems to me that this inside lisp

> ,------------------------
> | prg -'fun \"strg\" num'
> `------------------------
> How can I quote such a 'cmd' string in a way that it finally arrives as

should be this

> 
> ,------------------------
> | $ prg -'fun "strg" num'
> `------------------------

at the shell... No?

Anyway heres some (not too great) hacking:
(with my recently learnt from Bastien's C-j!) 

(setq cmd "prg -'fun \"strg\" num'")
"prg -'fun \"strg\" num'"
(setq x (split-string cmd "-"))
("prg " "'fun \"strg\" num'")
(setq p (car (split-string (car x))))
"prg"
(setq arg (cadr x))
"'fun \"strg\" num'"
; (make-comint "buffer-name" p nil (concat "-" arg))

Re: Shell argument quoting woes

[Thorsten Jolitz]

Rustom Mody <rustompmody@gmail.com> writes:

> On Thursday, July 25, 2013 7:00:32 PM UTC+5:30, Thorsten Jolitz wrote:
> Seems to me that this inside lisp
>
>> ,------------------------
>> | prg -'fun \"strg\" num'
>> `------------------------
>> How can I quote such a 'cmd' string in a way that it finally arrives as
>
> should be this
>
>> 
>> ,------------------------
>> | $ prg -'fun "strg" num'
>> `------------------------
>
> at the shell... No?
>
> Anyway heres some (not too great) hacking:
> (with my recently learnt from Bastien's C-j!) 
>
> (setq cmd "prg -'fun \"strg\" num'")
> "prg -'fun \"strg\" num'"
> (setq x (split-string cmd "-"))
> ("prg " "'fun \"strg\" num'")
> (setq p (car (split-string (car x))))
> "prg"
> (setq arg (cadr x))
> "'fun \"strg\" num'"
> ; (make-comint "buffer-name" p nil (concat "-" arg))

I see, so the problem was actually the string-splitting by spaces and
not the quoting. Thanks!

-- 
cheers,
Thorsten

Re: Shell argument quoting woes

[Rustom Mody]

On Thursday, July 25, 2013 8:58:51 PM UTC+5:30, Thorsten Jolitz wrote:
> I see, so the problem was actually the string-splitting by spaces and
> not the quoting. Thanks!

Actually ideal would be to split on only 1st space(s).
In languages like python this is possible.
I guess you can do it with a regexp in elisp:

Python 2.7.5+ (default, Jun  2 2013, 21:21:29) 
[GCC 4.7.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> cmd="prg -'fun \"strg\" num'"
>>> cmd.split(" ", 1)
['prg', '-\'fun "strg" num\'']