PETSC_ARCH variable --> PETSC_CONF

[Boyana Norris]

On Nov 30, 2009, at 3:59 PM, Barry Smith wrote:

>
> On Nov 30, 2009, at 3:51 PM, Boyana Norris wrote:
>
>> Why not recognize both? It's fairly trivial to check for PETSC_CONF  
>> if PETSC_ARCH is undefined and internally define PETSC_ARCH using  
>> PETSC_CONF.
>
>  This is a make variable. I am not sure that it is trivial to check  
> if a variable is set and use something else otherwise in a tidy way  
> in make. Plus I had the idea of having two variables that mean the  
> same thing.

There are a couple of different ways, e.g., one is

ifndef PETSC_ARCH
  ifdef PETSC_CONF
   PETSC_ARCH=$(PETSC_CONF)
  else
   $(error "Make sure the PETSC_CONF environment variable is defined  
before running make.")
  endif
endif

This is for GNU make, which is pretty widely available, and may have  
to be adjusted for ancient systems.

Boyana

>
>  Barry
>
>
>>
>> Boyana
>>
>> --
>> Boyana Norris, Computer Scientist, Argonne National Laboratory
>> norris at mcs.anl.gov, +1.630.252.7908, http://www.mcs.anl.gov/~norris/
>>
>> On Nov 30, 2009, at 3:43 PM, Matthew Knepley wrote:
>>
>>> On Mon, Nov 30, 2009 at 3:38 PM, Barry Smith <bsmith at mcs.anl.gov>  
>>> wrote:
>>>
>>>  I guess the argument is that on occasion in the future a certain  
>>> number of people will misinterpret the meaning of PETSC_ARCH  
>>> frustrating them and us; the number misinterpreting PETSC_CONF  
>>> will be much smaller or zero saving people's time and energy.
>>>
>>> This will be far outweighed by the number of people complaining  
>>> about such a change. I agree with them.
>>>
>>>  Matt
>>>
>>>  Barry
>>>
>>>
>>> On Nov 30, 2009, at 3:25 PM, Matthew Knepley wrote:
>>>
>>> I see the point, but this is one of the oldest parts of PETSc, and  
>>> I am hesitant to change one
>>> arbitrary name to another without a more convincing reason.
>>>
>>>  Matt
>>>
>>> On Mon, Nov 30, 2009 at 2:17 PM, Barry Smith <bsmith at mcs.anl.gov>  
>>> wrote:
>>>
>>> Lisandro has pointed out to me several times that the variable  
>>> name PETSC_ARCH can be confusing; some people may think it is  
>>> related to the architecture of the machine and don't understand  
>>> that it is an arbitrary name that the user can make up. He  
>>> suggested changing it to PETSC_CONF to be clearer.
>>>
>>> Should we change it? Use something else?
>>>
>>>   Barry
>>>
>>>
>>>
>>>
>>> -- 
>>> What most experimenters take for granted before they begin their  
>>> experiments is infinitely more interesting than any results to  
>>> which their experiments lead.
>>> -- Norbert Wiener
>>>
>>>
>>>
>>>
>>> -- 
>>> What most experimenters take for granted before they begin their  
>>> experiments is infinitely more interesting than any results to  
>>> which their experiments lead.
>>> -- Norbert Wiener
>>
>