I guess I forgot to commit the makefile for libnetmon.

pelab/libnetmon/GNUmakefile

+SYSTEM :=	$(shell uname -s)
+
+# I like using -pedantic, but it gives us some trouble with function pointers
+CFLAGS=-Wall -Werror
+
+ifeq ($(SYSTEM),Linux)
+    LD_FLAGS=-ldl
+else
+    LD_FLAGS=
+endif
+
+all: libnetmon.so
+
+%.so: %.c %.h
+	$(CC) $(CFLAGS) $(LD_FLAGS) -shared -o $@ $<
+
+clean:
+	-rm *.so