:: Re: [DNG] leveldb support proposal
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Skribent: Rainer Weikusat
Dato:  
Til: dng
Emne: Re: [DNG] leveldb support proposal
Didier Kryn <kryn@???> writes:
> Le 01/03/2016 11:37, Noel Torres a écrit :
>> It happens a lot that two packages you need request different
>> versions of the same library, not always co-installable. Mostly if
>> you go beyond "stable". Or even if you got stuck on oldstable and
>> try to install some simple new package.
>>
>> And this is a good amount of the "dependency hell" when it comes to
>> Desktop users.
>>
>> So, I think that having some way of installing multiple versions of
>> the same library would be a useful feature. Heck, even windows does
>> that in (some) right way.
>
>     I hesitated to reply because I know my answer is politically
> incorrect. "dependency hell" is the consequence of dynamic linkage.


The term 'dll hell' which gave birth to the other originally referred to
different Windows applications bundling different version of the same
system DLL such that installing an application could break unrelated
applications because these weren't compatible with the system DLL
version bundled with the new application.

But that's a problem which simply doesn't exist on Linux-based systems
because which application will be runtime linked with which libraries
can be controlled in various ways both for applications compiled on a
system and applications shipped as binaries[*]. That's just a matter of
application authors documenting their depedencies and trusting on
sysadmins/ users to meet them.

[*] One of the less-than-pleasant things I had to do in the past was get
    a proprietary "Linux application" which was compiled for "Linux" aka
    "some unknown, dated version of Fedora" to work on a much newer
    Ubuntu "short-term" release. This was intricate enough to require
    running the program in a chroot environment providing compatible
    library versions.