Okay D'Arcy...found a purpose to Makefile.custom *grin*:

scrappy · scrappy · commit 457ed3d9c61d · 1996-10-25T09:26:56.000Z
# If your OS requires these libraries, they should be put in
# Makefile.custom with a line similar to:
# X11_LIB+= -lsocket -lnsl

Actually, those should probably go into the ports/Makefile.inc's, but...
diff --git a/src/Makefile.global b/src/Makefile.global
@@ -7,7 +7,7 @@
 #
 #
 # IDENTIFICATION
-#    $Header: /cvsroot/pgsql/src/Attic/Makefile.global,v 1.19.2.12 1996/10/25 09:24:56 scrappy Exp $
+#    $Header: /cvsroot/pgsql/src/Attic/Makefile.global,v 1.19.2.13 1996/10/25 09:26:56 scrappy Exp $
 #
 # NOTES
 #    This is seen by any Makefiles that include mk/postgres.mk. To
@@ -226,7 +226,10 @@ TK_LIB = -ltk4.1
 
 X11_INCDIR = /usr/include
 X11_LIBDIR = /usr/lib
-X11_LIB = -lX11 -lsocket -lnsl
+# If your OS requires these libraries, they should be put in
+# Makefile.custom with a line similar to:
+# X11_LIB+= -lsocket -lnsl
+X11_LIB = -lX11 
 
 #
 # include port specific rules and variables. For instance:

Original file line number	Diff line number	Diff line change
`@@ -7,7 +7,7 @@`
`7`	`7`	`#`
`8`	`8`	`#`
`9`	`9`	`# IDENTIFICATION`
`10`		`-# $Header: /cvsroot/pgsql/src/Attic/Makefile.global,v 1.19.2.12 1996/10/25 09:24:56 scrappy Exp $`
	`10`	`+# $Header: /cvsroot/pgsql/src/Attic/Makefile.global,v 1.19.2.13 1996/10/25 09:26:56 scrappy Exp $`
`11`	`11`	`#`
`12`	`12`	`# NOTES`
`13`	`13`	`# This is seen by any Makefiles that include mk/postgres.mk. To`
`@@ -226,7 +226,10 @@ TK_LIB = -ltk4.1`
`226`	`226`
`227`	`227`	`X11_INCDIR = /usr/include`
`228`	`228`	`X11_LIBDIR = /usr/lib`
`229`		`-X11_LIB = -lX11 -lsocket -lnsl`
	`229`	`+# If your OS requires these libraries, they should be put in`
	`230`	`+# Makefile.custom with a line similar to:`
	`231`	`+# X11_LIB+= -lsocket -lnsl`
	`232`	`+X11_LIB = -lX11`
`230`	`233`
`231`	`234`	`#`
`232`	`235`	`# include port specific rules and variables. For instance:`