Emacs fails to use default locale

Emacs fails to use default locale

[Ken Brown]

According to

   http://www.opengroup.org/onlinepubs/007908799/xbd/envvar.html

if LC_ALL, LC_CTYPE, and LANG are all either unset or empty, then the 
implementation-dependent default locale is supposed to be used.  My 
understanding is that this should be done by using setlocale(LC_CTYPE, 
"").  But emacs's locale initialization seems to just use the 
environment variables, so it doesn't pick up the default locale if the 
variables are unset.

Ken

Re: Emacs fails to use default locale

[Jan Djärv]

Ken Brown skrev:
> According to
> 
>   http://www.opengroup.org/onlinepubs/007908799/xbd/envvar.html
> 
> if LC_ALL, LC_CTYPE, and LANG are all either unset or empty, then the 
> implementation-dependent default locale is supposed to be used.  My 
> understanding is that this should be done by using setlocale(LC_CTYPE, 
> "").  But emacs's locale initialization seems to just use the 
> environment variables, so it doesn't pick up the default locale if the 
> variables are unset.
> 

setlocale(LC_ALL, "") is the way.  Emacs does that if LC_ALL is unset or not "C".

However, because of internal reasons, Emacs also does:
   /* The Emacs Lisp reader needs LC_NUMERIC to be "C",
      so that numbers are read and printed properly for Emacs Lisp.  */
   setlocale (LC_NUMERIC, "C");

Can you describe in more detail the problem you are seeing?  I.e. what output 
is wrong?

	Jan D.

Re: Emacs fails to use default locale

[Ken Brown]

On 11/27/2009 10:49 AM, Jan Djärv wrote:
> Ken Brown skrev:
>> According to
>>
>>   http://www.opengroup.org/onlinepubs/007908799/xbd/envvar.html
>>
>> if LC_ALL, LC_CTYPE, and LANG are all either unset or empty, then the 
>> implementation-dependent default locale is supposed to be used.  My 
>> understanding is that this should be done by using setlocale(LC_CTYPE, 
>> "").  But emacs's locale initialization seems to just use the 
>> environment variables, so it doesn't pick up the default locale if the 
>> variables are unset.
>>
> 
> setlocale(LC_ALL, "") is the way.  Emacs does that if LC_ALL is unset or 
> not "C".
> 
> However, because of internal reasons, Emacs also does:
>   /* The Emacs Lisp reader needs LC_NUMERIC to be "C",
>      so that numbers are read and printed properly for Emacs Lisp.  */
>   setlocale (LC_NUMERIC, "C");
> 
> Can you describe in more detail the problem you are seeing?  I.e. what 
> output is wrong?

I'm working in Cygwin 1.7, which has recently adopted a default locale 
that uses UTF-8 encoding.  If I start emacs with none of the locale 
variables set, emacs appears to assume an ASCII character set.  (I don't 
see "U" in the  mode line, for instance.)  Moreover, C-h C returns the 
error message "Unknown button type `help-xref'".

When I referred to emacs's locale initialization in my original post, I 
was referring to the code in lisp/international/mule-cmds.el.  I don't 
really understand how this interacts with the setlocale calls.

Here's one further bit of information:  If I evaluate (getenv "LANG") in 
  the scratch buffer, it returns nil (as expected), but then C-h C 
suddenly works.  And it tells me that the default coding system is nil, 
so it clearly hasn't picked up the system default.

Ken

Re: Emacs fails to use default locale

[Ken Brown]

On 11/27/2009 1:06 PM, Ken Brown wrote:
> On 11/27/2009 10:49 AM, Jan Djärv wrote:
>> Ken Brown skrev:
>>> According to
>>>
>>>   http://www.opengroup.org/onlinepubs/007908799/xbd/envvar.html
>>>
>>> if LC_ALL, LC_CTYPE, and LANG are all either unset or empty, then the 
>>> implementation-dependent default locale is supposed to be used.  My 
>>> understanding is that this should be done by using 
>>> setlocale(LC_CTYPE, "").  But emacs's locale initialization seems to 
>>> just use the environment variables, so it doesn't pick up the default 
>>> locale if the variables are unset.
>>>
>>
>> setlocale(LC_ALL, "") is the way.  Emacs does that if LC_ALL is unset 
>> or not "C".
>>
>> However, because of internal reasons, Emacs also does:
>>   /* The Emacs Lisp reader needs LC_NUMERIC to be "C",
>>      so that numbers are read and printed properly for Emacs Lisp.  */
>>   setlocale (LC_NUMERIC, "C");
>>
>> Can you describe in more detail the problem you are seeing?  I.e. what 
>> output is wrong?
> 
> I'm working in Cygwin 1.7, which has recently adopted a default locale 
> that uses UTF-8 encoding.  If I start emacs with none of the locale 
> variables set, emacs appears to assume an ASCII character set.  (I don't 
> see "U" in the  mode line, for instance.)  Moreover, C-h C returns the 
> error message "Unknown button type `help-xref'".
> 
> When I referred to emacs's locale initialization in my original post, I 
> was referring to the code in lisp/international/mule-cmds.el.

Maybe the problem (or at least part of the problem) is that mule-cmds.el 
doesn't call (locale-info 'codeset) when the CODESET can't be determined 
  from environment variables.

Ken