Troubling compiling with pthread

I am writing a program that uses threads. Everything compiles fine, but when I run the program, I get the following error:
Shared object "libpthread.so.20" not found

Here's what I have in my makefile:

Code:

---

files = thread thread.core temp output
includes = -I/usr/pkg/include
lib = -L/usr/pkg/lib
library = -lpthread

make:
        gcc thread.c $(lib) $(includes) $(library) -o thread
        ./thread -p 23 -c 3 -n 10 -t 5 -s 6

clean:
        @for file in $(files); do \
                if [ -f $$file ] ; then\
                        echo "rm $$file"; \
                        rm $$file; \
                fi; \
        done;

---

I am doing my work on NetBSD 1.6.1. Can someone help me out?

do you have libpthread.so.20 on your system (find/locate)?

do your default library paths contain it's directory (/etc/ld.so.conf)?

Yes I have all the threading libraries. I solved the problem by doing setting LD_RUN_PATH to /usr/pkg/lib. Is there another way to do it? Thanks.