Re: added pkg-config script - Mailing list pgsql-patches

On Sun, Aug 22, 2004 at 11:39:38AM -0700, Stephan Szabo wrote:
>
> On Sun, 22 Aug 2004, Czuczy Gergely wrote:
>
> > I've attached a corrected patch, the postgresql.pc.in was missing.
> >
> > On Sun, Aug 22, 2004 at 01:49:08PM -0400, Tom Lane wrote:
> > > phoemix@harmless.hu (Czuczy Gergely) writes:
> > > > I've added a pkg-config script.
> > > > The "diff -rc -x configure from to" output is attached.
> > >
> > > Considering that this patch is lacking both the script itself, and any
> > > documentation, it's not got much hope of being accepted...
> > What kind of documentation does it need? i don't see.
>
> Well, you've added a configure option, so the installation sgml at the
> very least.  If it's meant to replace or do the same general thing as
> pg_config, then the places pg_config is mentioned in mainline docs should
> probably be added to as well (libpq and xfunc).
not replaces, just an alternative.

>
> > > But before you run off to produce those things, I would suggest
> > > putting up a proposal on pghackers about what you want to do
> > > and why.  In particular, what problem are you solving that isn't
> > The most common way to get a package's libflags and cflags is the solution
> > that pkg-config offers. the problem with pg_config that it's not in the path,
> > it's place depends on the prefix, so to use it required an extra effort.
> > pkg-config is a standardized way to check for a package's libs and cflags.
> > The patch I've made adds the generation of this script, and extends the Makefiles
> > to install them. The place of this .pc (Pkg-Config) file is at /usr/lib/pkgconfig/,
> > but with the patch it can be altered with --with-pkgconfig-dir.
>
> How is the pkg-config stuff meant to interact with having multiple
> different installations on a machine? I might, for example, have two or
> three copies of the same version of postgresql with different options
> under some circumstances.
it doesn't. pkg-config is a very simple thing, good for generalism. what
you are talking about is an extrem environment, as I noticed, less then
1% of the users have this. on the other side the vast majority's configure, pmk,
and so on scripts do not find the required config script, because it's out-of-path,
and has to be given by hand. for these situation pkg-config provides a simple
solution, adds a general file to the place, and whenever a configure/pmk/etc script
needs the libs/cflags/so on it can ask pkg-config for it. no need to search for
pg_config's location. anyway, if you want to have multiple installations, it can be
solved but that will break the generalism that pkg-config provides. adding some
kind of suffix to the .pc file, like postgresql-myinstance.pc, or so. But, as I've
said it will break the generalism, because the configure/pmk/etc scripts look for
'postgresql', not 'postgresql-myinstance'.

Bye,

Gergely Czuczy
mailto: phoemix@harmless.hu
PGP: http://phoemix.harmless.hu/phoemix.pgp

Weenies test. Geniuses solve problems that arise.