| 1 |
On 29.11.2012 21:11, Ralph Sennhauser wrote: |
| 2 |
> On Thu, 29 Nov 2012 17:09:34 +0100 |
| 3 |
> justin <jlec@g.o> wrote: |
| 4 |
> |
| 5 |
>> On 29/11/12 16:51, Ian Stakenvicius wrote: |
| 6 |
> [...] |
| 7 |
>>> ..ok remind me again what the .pc files provide you? this is so |
| 8 |
>>> that you can have slotted blas providers and various packages can |
| 9 |
>>> choose their preferred one instead of having to use the eselected |
| 10 |
>>> one? or... |
| 11 |
>>> |
| 12 |
>> |
| 13 |
>> Not exactly. |
| 14 |
>> The user can choose for each package newly by eselecting the wanted |
| 15 |
>> implementation. This is the user side. From the pm side we ensure that |
| 16 |
>> the choice is really respected by linking against package specific |
| 17 |
>> names [1] instead of the generic ones e.g. libblas.so. And this can be |
| 18 |
>> achieved in an easy way by using pkg-config. |
| 19 |
>> |
| 20 |
>> justin |
| 21 |
>> |
| 22 |
>> 1) |
| 23 |
>> # eselect blas set atlas-threads |
| 24 |
>> # pkg-config --libs blas |
| 25 |
>> -lptf77blas -lm -latlas -lpthread |
| 26 |
>> |
| 27 |
>> # eselect blas set reference |
| 28 |
>> # pkg-config --libs blas |
| 29 |
>> -lrefblas |
| 30 |
>> |
| 31 |
> |
| 32 |
> This immediately bears the following questions: |
| 33 |
> |
| 34 |
> * How do you ensure the linked against implementation doesn't get |
| 35 |
> depcleaned? revdep-rebuild maybe? |
| 36 |
|
| 37 |
portage handles this fine. |
| 38 |
|
| 39 |
> |
| 40 |
> * How do you let users configure the implementation to be used on a per |
| 41 |
> package basis? Interrupt an emerge world to set the appropriate |
| 42 |
> implementation for the next few packages? |
| 43 |
> |
| 44 |
|
| 45 |
The Standard user will get reference implementation and has no problem. |
| 46 |
Setting individual implementation on per package basis needs to be |
| 47 |
considered as they-know-what-they-are-doing. Otherwise you don't know |
| 48 |
which implementation to choose . |
Archives