Unsure but perhaps these are involved, what are your setting for:

org-src-preserve-indentation

and

org-edit-src-content-indentation

On Sun, Jan 11, 2015 at 12:30 PM, Giuseppe Lipari <giulipari@gmail.com>
wrote:

> Dear Eric,
>
> thanks for your quick answer. However this does not solve the problem.
> I use source code fontification for source blocks in org mode:
>
> #+begin_src emacs-lisp
>   (setq org-src-fontify-natively  t)
>   (setq org-src-tab-acts-natively t)
> #+end_src
>
>
> Normally, when I program in C or java, I disable indent-tabs mode. So, I
> have this hook
>
>  (add-hook 'java-mode-hook (lambda ()
>                               (setq c-basic-offset 4
>                                     tab-width 4
>                                     indent-tabs-mode nil)))
>
> somewhere in my init file.
>
> If I understand well what "org-src-fontify-natively" means, it should call
> the hook when I edit a code block whose language is Java, and this should
> in turn set the variable to nil. In fact, no tab is ever inserted anywhere
> in my org file, and the value od "indent-tabs-mode" at the buffer local
> level is nil, exactly as in your case. I have no idea if it can be set to
> nil at the global level (the documentation seems to say that it is not
> possible).
>
> Summarising
>
>     no tab in the org file, --> a tab appears in the tex file
>
> Thanks anyway.
>
> Giuseppe Lipari
>
>
>
>
> 2015-01-11 19:01 GMT+01:00 Eric S Fraga <e.fraga@ucl.ac.uk>:
>
>> On Sunday, 11 Jan 2015 at 17:31, Giuseppe Lipari wrote:
>>
>> [...]
>>
>> > There is not tab in this snipper (I never use tabs in code, only
>> spaces).
>> > Unfortunately, when opening the tex file, I see that a tab has been
>> > introduced whenever 8 consecutive spaces are found, in particular at
>> line 4.
>>
>> Shot in the dark: are tabs inserted when code is auto-indented?  If so,
>> maybe:
>>
>> ,----[ C-h v indent-tabs-mode RET ]
>> | indent-tabs-mode is a variable defined in `C source code'.
>> | Its value is nil
>> | Original value was t
>> | Local in buffer *unsent wide reply to Giuseppe Lipari*; global value is
>> the same.
>> |
>> |   Automatically becomes buffer-local when set.
>> |   This variable is safe as a file local variable if its value
>> |   satisfies the predicate `booleanp'.
>> |
>> | Documentation:
>> | Indentation can insert tabs if this is non-nil.
>> |
>> | You can customize this variable.
>> |
>> `----
>>
>> --
>> : Eric S Fraga (0xFFFCF67D), Emacs 25.0.50.1, Org
>> release_8.3beta-703-gef523b.dirty
>>
>
>
>
> --
> Giuseppe Lipari
> LIFL
> Université de Lille 1
> blogs: http://scacciamennule.blogspot.com  (Italian)
> <http://scacciamennule.blogspot.com>
>           http://okpanico,wordpress.com          (Italian)
>           http://algoland.wordpress.com           (English)
>



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