No output from executable using JNI

Hi, Guys -
New to JNI, have a question: I can get both my C and Java code to compile, a .dll to build, and the program to run, but I get no output. Execution seems to endl at the System.loadLibrary() call. I've tried to get it running in both cmd and cygwin windows without success.
Any ideas?
Thanks.
----- Environment/platform/makefile info ------
Win2kPro
Java 1.4.1
DCTAgent.class: DCTAgent.java
     ${JAVA_DIR}/javac DCTAgent.java
     ${JAVA_DIR}/javah -jni -d ./include DCTAgent
DCTAgentImp.dll: DCTAgentImp.c
     ${CC} -D__int64="long long" ${PCAP_INCLUDE} ${JAVA_INCLUDE} -mrtd -g -c DCTAgentImp.c
     ${CC} ${PCAP_INCLUDE} ${JAVA_INCLUDE} -shared -g -o DCTAgentImp.dll DCTAgentImp.o
----- Java code ------
public class DCTAgent {
public native void hello();
private void helloWorld() {
System.err.println("calling hello() native...");
hello();
System.err.println("... done!");
static {
System.err.println("loading...");
System.loadLibrary("DCTAgentImp");
public static void main(String[] args) {
new DCTAgent().helloWorld();
----- C file ------
#include <jni.h>
#include "include/DCTAgent.h"
#include <stdio.h>
JNIEXPORT void JNICALL Java_DCTAgent_hello (JNIEnv *env, jobject obj) {
printf("\nHello world!");
return;
----- C header ------
/* DO NOT EDIT THIS FILE - it is machine generated */
#include <jni.h>
/* Header for class DCTAgent */
#ifndef IncludedDCTAgent
#define IncludedDCTAgent
#ifdef __cplusplus
extern "C" {
#endif
* Class: DCTAgent
* Method: hello
* Signature: ()V
JNIEXPORT void JNICALL Java_DCTAgent_hello
(JNIEnv *, jobject);
#ifdef __cplusplus
#endif
#endif
----- output ------
$ c:/~path.to.java~/java -Djava.library.path=C:\mypath DCTAgent
loading...
$

Your problem sounds a lot like I was having until about an hour ago when I found this:
http://www.cygwin.com/ml/cygwin/2004-04/msg00099.html
The short answer (originally posted by Igor Pechtchanski) is to set the flag
-mno-cygwin
when you are linking your DLL.
To do this you need to install the packages "gcc-mingw" and "mingw-runtime" in your cygwin installation.
The reason for the problem is apparently that cygwin1.dll cannot be dynamically loaded, and programs will hang if/when they try to dynamically load it. If your DLL does not require the POSIX functions found in cygwin1.dll, you can force the equivalent of a mingw-compiled DLL with that flag, and cygwin1.dll will not be dynamically loaded.
It works like a charm for me, and has solved my problems with calling C++ code from JNI, as well as calling C++ code from Matlab (through an intermediary C DLL, although I think there are ways to eliminate that as well). Hope that helps.

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