Dave, the relevant place to look for the client library is the command used for building/linking.
To link with the client library from mac ports, i use under MacPorts Mavericks and Yosemite
make PGLIB=/opt/local/lib/postgresql94/ PGINCLUDE=/opt/local/include/postgresql94/
use the following command under Mac OS X to see, which client libaries you are using on your installation:
% otool -L nsdbpg.so
nsdbpg.so:
/usr/local/ns/lib/libnsdb.dylib (compatibility version 0.0.0, current version 0.0.0)
/opt/local/lib/postgresql94/libpq.5.dylib (compatibility version 5.0.0, current version 5.7.0)
/usr/local/ns/lib/libnsthread.dylib (compatibility version 0.0.0, current version 0.0.0)
/usr/local/ns/lib/libnsd.dylib (compatibility version 0.0.0, current version 0.0.0)
/usr/local/ns/lib/libtcl8.5.dylib (compatibility version 8.5.0, current version 8.5.17)
/usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current version 1213.0.0)
No warpper etc. is needed.
