[yocto] Busybox sh link

[ChenQi]

On 11/19/2014 12:34 AM, Stefan Eichenberger wrote:
> On 11/18/2014 04:07 AM, ChenQi wrote:
>> On 11/17/2014 10:07 PM, Stefan Eichenberger wrote:
>>> Hello all
>>>
>>> I have a question regarding busybox and sh. If I want to install 
>>> bash together with busybox ash, yocto does not consider the 
>>> ALTERNATIVE_PRIORITY in each case (e.g. if bash is installed before 
>>> busybox). The problem is that do_install of busybox creates a link 
>>> to busybox.nosuid. Is there a reason for that? Shouldn't 
>>> update-alternatives create that link for us? There is already a 
>>> patch available that targets this problem 
>>> (467b19efbaa9c0cb04d2665e8cd9a0919849a5ed ) but it only works if ash 
>>> is completely disabled in the busybox config.
>>>
>>> So the main question is, wouldn't it be possible to remove this 
>>> lines completely?
>>>
>>> Regards,
>>> Stefan
>>>
>>>
>>
>> I can confirm that this is indeed a problem. And we need to fix this.
>> I think the reason for this line is mainly to make 'busybox' provide 
>> '/bin/sh' so that do_rootfs would succeed.
>>
>> Regards,
>> Chen Qi
>
> Probably I miss something but I don't understand why do_rootfs fails 
> if the link is not provided? Isn't the link created anyhow during 
> package installation in the postinstall script with 
> update-alternatives if necessary?
>
> For testing I removed the link creation temporary from the recipe and 
> built the core-image-minimal for qemux86, it was creating the link 
> correctly in this case.
>
> Regards,
> Stefan
>
>

Hi Stefan,

I did some testing, and could not reproduce the problem.
I then realized that as the sh link is managed by ALTERNATIVES 
mechanism, it will always point to bash instead of busybox.

I tested it by the following steps:
1. build core-image-minimal with bash installed
2. reinstall bash
3. reinstall busybox

So I think the current code is right.

I'm not sure if I missed something. If so, could you please provide more 
information?

Best Regards,
Chen Qi