miskatonic:local root# gem install postgres -- --with-pgsql-include-dir=/opt/local/include/postgresql83 --with-pgsql-lib-dir=/opt/local/lib/postgresql83 --with-pgsql-bin-dir=/opt/local/lib/postgresql83/bin
Building native extensions.  This could take a while...
ERROR:  Error installing postgres:
	ERROR: Failed to build gem native extension.

/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/bin/ruby extconf.rb install postgres -- --with-pgsql-include-dir=/opt/local/include/postgresql83 --with-pgsql-lib-dir=/opt/local/lib/postgresql83 --with-pgsql-bin-dir=/opt/local/lib/postgresql83/bin
extconf.rb:73: command not found: pg_config --bindir

		===========   WARNING   ===========

		You are building this extension on OS X without setting the
		ARCHFLAGS environment variable, and PostgreSQL does not appear
		to have been built as a universal binary. If you are seeing this
		message, that means that the build will probably fail.

		Try setting the environment variable ARCHFLAGS
		to '-arch i386' before building.

		For example:
		(in bash) $ export ARCHFLAGS='-arch i386'
		(in tcsh) $ setenv ARCHFLAGS '-arch i386'

		Then try building again.

		===================================
		extconf.rb:46: command not found: pg_config --includedir
extconf.rb:53: command not found: pg_config --libdir
checking for main() in -lpq... no
Could not find PostgreSQL build environment (libraries & headers): Makefile not created

make
gcc -I. -I. -I/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/universal-darwin9.0 -I. -DHAVE_LIBPQ_FE_H -DHAVE_LIBPQ_LIBPQ_FS_H -I/usr/local/pgsql/include  -fno-common -arch ppc -arch i386 -Os -pipe -fno-common  -c libpq-compat.c
libpq-compat.c: In function 'PQescapeBytea':
libpq-compat.c:104: warning: incompatible implicit declaration of built-in function 'sprintf'
libpq-compat.c:104: warning: pointer targets in passing argument 1 of 'sprintf' differ in signedness
libpq-compat.c: In function 'PQunescapeBytea':
libpq-compat.c:158: warning: incompatible implicit declaration of built-in function 'strlen'
libpq-compat.c:158: warning: pointer targets in passing argument 1 of 'strlen' differ in signedness
libpq-compat.c: In function 'PQescapeBytea':
libpq-compat.c:104: warning: incompatible implicit declaration of built-in function 'sprintf'
libpq-compat.c:104: warning: pointer targets in passing argument 1 of 'sprintf' differ in signedness
libpq-compat.c: In function 'PQunescapeBytea':
libpq-compat.c:158: warning: incompatible implicit declaration of built-in function 'strlen'
libpq-compat.c:158: warning: pointer targets in passing argument 1 of 'strlen' differ in signedness
libpq-compat.c:227:22: error: libpq-fe.h: No such file or directory
libpq-compat.c: At top level:
libpq-compat.c:232: error: syntax error before '*' token
libpq-compat.c:232: error: syntax error before '*' token
libpq-compat.c: In function 'PQexecParams_compat':
libpq-compat.c:235: error: 'command' undeclared (first use in this function)
libpq-compat.c:235: error: (Each undeclared identifier is reported only once
libpq-compat.c:235: error: for each function it appears in.)
libpq-compat.c:241: error: 'values' undeclared (first use in this function)
libpq-compat.c:251: error: 'conn' undeclared (first use in this function)
libpq-compat.c:251: warning: return makes pointer from integer without a cast
libpq-compat.c:227:22: error: libpq-fe.h: No such file or directory
libpq-compat.c: At top level:
libpq-compat.c:232: error: syntax error before '*' token
libpq-compat.c:232: error: syntax error before '*' token
libpq-compat.c: In function 'PQexecParams_compat':
libpq-compat.c:235: error: 'command' undeclared (first use in this function)
libpq-compat.c:235: error: (Each undeclared identifier is reported only once
libpq-compat.c:235: error: for each function it appears in.)
libpq-compat.c:241: error: 'values' undeclared (first use in this function)
libpq-compat.c:251: error: 'conn' undeclared (first use in this function)
libpq-compat.c:251: warning: return makes pointer from integer without a cast
lipo: can't open input file: /var/tmp//ccJlBvPk.out (No such file or directory)
make: *** [libpq-compat.o] Error 1


Gem files will remain installed in /Library/Ruby/Gems/1.8/gems/postgres-0.7.9.2008.01.28 for inspection.
Results logged to /Library/Ruby/Gems/1.8/gems/postgres-0.7.9.2008.01.28/ext/gem_make.out