Re: [fuse-devel] Do I need to support both - libfuse2 and libfuse3 in my application in order to work on more Linux distros, in case I deploy libfuse with my application

[Antonio SJ M. <tra...@sp...>]

You can optionally deploy it or patch the build to install to a 
different location / filename.

This is what I was getting at prior. The library is not designed to be 
used this way so without upstreaming some changing that make it easier 
to do so you'll have to maintain some part of the setup.

My biggest problem with embedding libfuse3 was the build system simply 
not working on older platforms and getting that replaced or officially 
supporting multiple systems doesn't seem a reasonable ask.

On 10/1/2019 7:31 AM, Cyril Cyrov wrote:
> Actually, deploying `libfuse3.so` won't be enough, deploying
> `fusermount3` is also necessary (+ building libfuse with `-D
> FUSERMOUNT_DIR=.....`)? Isn't this some kind of a security issue
> (deploying fusermount3)?
>
> On Tue, Oct 1, 2019 at 1:53 PM Cyril Cyrov <cyr...@gm...> wrote:
>> Hi,
>>
>> Here's an introduction for this thread:
>> https://github.com/libfuse/libfuse/issues/460
>>
>> Long story short:
>> Q: How can I support both libfuse2 and libfuse3 in order to make my
>> app work on more Linux distos?
>> A: You don't need to do that.
>>
>> So, continuing the discussion here.
>>
>> ---
>>
>> My misunderstanding comes from the fact, that I though there are two
>> different kernel modules for the two versions and that libfuse3 can
>> only work on Linux distros, which do have `fuse3` package installed
>> (and these distros are just a few). This misunderstanding was also
>> supported by the fact, that libfuse3 needs fusermount3 in order to
>> create a mountpoint.
>>
>> Another miscommunication occurred by the different interpretation of
>> "patching the fuse implementation" and "embedding" fuse.
>>
>> We do deploy a libfuse shared object with our application. So, this is
>> not an issue at all.
>>
>> My concern was - can I use and deploy libfuse3 on older Linux distros,
>> like CentOS 6, for example?
>>
>> What confuses me further is that I cannot find any matching between
>> libfuse versions and kernel versions, explaining which libfuse version
>> is compatible with which kernel versions.
>>
>> ---
>>
>> @trapexit
>>> Then you'll have to deal with the distro's support
>> By "avoid patching the fuse implementation" I didn't mean I don't want
>> to deploy fuse build, I just misunderstood you and thought that you
>> suggest actually making some source patch in order to "merge" them
>> somehow. Sorry for the misleading.
>>
>> ---
>>
>> @Nikratio:
>>> "Why don't you ship two binaries (one for libfuse2 and one for libfuse3) together with a small wrapper that picks with version to use?"
>> This will be necessary only if we don't deploy a build for libfuse, correct?
>>
>> ---
>>
>> So, I'll try to wrap things up, please correct me if I'm wrong - appreciated!
>>
>> We can actually use only libfuse3 and if we deploy it (or statically
>> link it in our application) this should work fine all Linux distros,
>> which otherwise would work fine with libfuse2. Is that correct?
>> Also, is there a way to find out which libfuse3 features depend on
>> which Linux kernel, in order to work fine?
>>
>> Thanks,
>> Kiril
>