Tom Thanks for the reply. My GSL libraries, 'libgsl' and 'libgslcblas', are in the /usr/lib directory as GSL and the GSL development files were installed via Fedora 8 RPM's. I'm a relative newbie to programming, so I thought the -L switch is only required to add a non-standard library location to the directories searched for libraries. I will give it a go. Thanks John Quoting Tom Lane <tgl@xxxxxxxxxxxxx>: > johnduffy@xxxxxxx writes: > > My functions compile fine using PGXS, but don't link against the GSL > libraries. > > How do I specify the GSL libraries as external libraries to link against in > the > > PGXS Makfile? I have tried the following which don't work: > > > PG_CPPFLAGS = -lgsl -lgslcblas > > PG_LIBS = -lgsl -gslcblas > > SHLIB_LINK = -lgsl -gslcblas > > > My PGXS makefile is: > > > MODULES pg_gsl > > PGXS := $(shell $(PG_CONFIG) --pgxs) > > include $(PGXS) > > SHLIB_LINK is the right thing for MODULES. Maybe you forgot a -L > switch? > > regards, tom lane > >