(huge) Ruby packaging changes

[Alexander Boström]

tor 2009-12-24 klockan 01:19 +0100 skrev Jeroen van Meeuwen:

> The beast that is Java ;-) A very successful example where alternatives
> is used heavily is of course a system's mail stack. I think it can be
> done right, but the question is how.
> 
> > On the other hand, if I got your intent right, environment-modules might be 
> > something to look into here.
> > 
> 
> Care to explain the term environment-modules for me please?

See Rahul's link, but it's a way to modify PATH, MANPATH etc. in a
structured way. The alternatives system is configured by root and
applies to everyone, the modules system is per-user or even per-process.

It sounds like your use case needs a per-user or per-process choice, so
I suggest you either use environment-modules or forego both modules and
the alternatives system and just teach users and packagers to call
ruby-1.8 instead of ruby when they need this version.

As mentioned, two typical uses of alternatives are:

Which MTA to use: Sendmail or something else? This is naturally root's
domain. Users shouldn't have to care.

Which Java to use: Mostly it's automatic. You install a bunch of Java
implementations and alternatives then picks the "best" one based on
priorities. Neither root nor users usually need to override it, but if
they want to they can, by adding /usr/lib/jvm/java-1.6.0-openjdk/bin or
similar to PATH, which is basically what modules does.

/abo