pkg-config for Lua and Linux/BSD distributions divergence

[Enrico Tassi <gareuselesinge@...>]

Lua 5.1 and lua 5.0 ship a pkg-config called just lua.pc, and all distributions
are forced to add a versioning extension to allow different versions of lua to
be installed at the same time. This lead to the usual divergence, in Debian it
is called lua5.1.pc, while IIRC just lua.pc on Fedora, and lua-5.1.pc on
FreeBSD. And our users are right to complain, while upstreams expecting lua to
be available have hard time checking for different .pc files in their
configure scripts.

I'm asking the lua team to change the name of such a file in their tarball, so
that all distributions can agree on a single (versioned) name. It is late for
lua 5.1, but with lua 5.2 you have the chance to make all distributions agree
an that name. 

The same problem arises for the name of the interpreter. In Debian we opted for
lua5.1, but I would not be surprised if there were distros shipping a lua51 or
lua-5.1 binary. Debian uses an system called alternatives to handle a 
symlink called lua to the real binary, thus users can run lua typing `lua`,
and have tools to chose the target of the symlink among all versions of 
lua installed. I think other distributions have a similar machinery too, to
allow different versions of the same binary to coexist.

Cheers
-- 
Enrico Tassi