[fluid-dev] Apt package dependencies -- WAS Re: Proposal: FluidSynth tester program

[jimmy]

--- On Sun, 8/5/12, Aere Greenway <address@hidden> wrote:

> Given the problems I had getting qjackctl to co-exist with
> the generated
> version of fluidsynth, I am puzzled by why I had no problems
> with my
> Ubuntu partition.  My guesses why are as follows:
> 
> 1. I had previously done some testing of a Rosegarden fix,
> and it has
> similar dependencies to fluidsynth.  Notably, it wants
> jackd1 (rather
> than jackd2, which qjackctl causes to be installed). 
> All this was
> in-place and working before I attempted to build
> fluidsynth.  
> 
> 2. I am using Ubuntu, rather than Xubuntu.


I don't use Ubunto, nor Xubuntu, so I don't know the current "version" various 
packages like libjack, qjackctl... and pre-requisites of each of those.

I use Debian Sid (Unstable repository), so the version of various packages 
available there are fairly recent.  For example qjackctl in Sid would probably 
want jackd2.

However, Debian Stable repository would (more likely) have much older "version" 
of qjackctl and related pre-requisite packages.

I mention that just as an example.  And everytime there is an update to the 
repository, some of those packages may require different pre-requisites.  So 
some of your currently installed packages will get out of sync with the 
repositories, until you decide to install the latest and greatest version for 
each of those packages.

In your case, it may not be fluidsynth and qjackctl which causes the dependency 
issues.  It might be some other music related packages that you were playing 
with.

I saw in one of your other posts mentioned:

   libjack-dev

which I believe might be a set of jack 1.x development header files.  If that 
is true, that package would require libjack 1.x libraries package, which cannot 
be installed concurrently with any jack 2.0 packages, at least from the 
perspective of the repository installation script when it tries to verify 
pre-requisites.

I suppose you were toying with some apps that was still using jack 1.0 sometime 
ago which needed the jack 1.0 header files to compile.  So that package was 
installed in the system was still there.

Currently, most music packages that use jack do use jack 2.x.  And the 
repository won't let you do that because jack 1.x and jack 2.x are mutully 
exclusive.  It won't automatically remove all of jack 1.x packages and 
additional packages which need jack 1.x.  The sticking point in your case was 
probably 

   libjack-dev

note that libjack-dev also need libjack0.  What you need to do is to explicitly 
remove all the jack 1.x packages, then go ahead and install any jack 2.x 
packages that you want.  The equivelance jack 2.x of that would be

   libjack-jackd2-dev

which needs libjack-jackd2-0 package.  When you try to remove all jack 1.x 
packages, it will also tell you what other packages were "also" to be removed, 
those would be the packages that depends on those jack 1.x packages.

After installing jack 2.x packages you want, you can try to manually install 
those packages (not Jack itself) which were removed when you remove jack 1.x.  
I run

   apt-get -d install somepackage

the "-d" say to download only.  Which will show you what packages it would 
install or remove if it is to install "somepackage".  If it won't remove any of 
the new jack 2.x packages, then I would let it completely download all the 
files it need.  Then run:

   apt-get install somepackage

which is the same command without the "-d" to go ahead and install 
"somepackage".

So yes, while you were removing and purging some of those packages, it finally 
remove enough of jack 1.x packages to let you install jack 2.x in the system.  
The reverse is also true.  If any packages which explicitely require some jack 
1.x but not compatible with jack 2.x will not install if jack 2.x is already in 
the system until you explicitely remove jack 2.x.

Jimmy