Thanks Alan. I have tried this out and it narrows the problem down somewhat. It seems to me that my problem is that I am running java from a rxvt and/or xterm. I'll bullet some observations:
* I normally enter commands into a bash shell running under a rxvt window. * When I ran the sample code from http://www.whitecaps.net/jni/expr.jar (here in known as expr code), it worked as expected. This is a strange exception that I'll comeback to. * Going back to the previous examples I was using, I rebuilt the dll in the same way as the build.xml from the expr code does. * Not using ant in this instance, I ran the example by entering the java command line directly. * The error changed in nature, but it was still a no-go. * Curiosity aroused, I went back to the expr code, and tried entering in the java command line (as per build.xml) into the rxvt and indeed, it failed in the same way. * I started up a Windows cmd prompt, copied and pasted the command-line, and it worked as it did under the ant build. * I started up a cmd prompt based Cygwin session, copied and pasted the command-line, and it worked as it did under the ant build. * Doing the same with my previous example worked as well. * Doing the same under Cygwin native xterm, in an xession failed in the same was as rxvt. So, I think it's safe to say, the problem has something to do with the terminal the Win32 native java interpreter is running under, and perhaps how cygwin handles pseudo-terminals??? But strangely, when run from within an ant process as mentioned, it worked ok. I just don't get it. Regards, Shaddy ----- Original Message ----- From: "Alan Thompson" <[EMAIL PROTECTED]> To: "Shaddy Baddah" <[EMAIL PROTECTED]>; <[EMAIL PROTECTED]> Sent: Thursday, May 22, 2003 5:54 AM Subject: Re: cygwin crashes when loading DLL > Shaddy - > > I have uploaded some sample code to http://www.whitecaps.net/jni/expr.jar . The expr/jni/hello directory contains a "standard" JNI example (where java calls into a C++ program) that works on Cygwin and has an ant buildfile (I assume you are using ant.....if not, get it and you'll be happy). The expr/jni/invoke directory has an example using the JNI invocation interface, where a C++ program creates a JVM to print "hello". Output is pasted below. > > Also, if you haven't seen it, look at the excellent writeup on JNI for Cygwin at http://www.inonit.com/cygwin/ > > Alan Thompson > > **************************************************************************** ************************ > > cd expr/jni/hello > ant > > Buildfile: build.xml > > clean: > > init: > [mkdir] Created dir: C:\export\expr\jni\hello\bin > [mkdir] Created dir: C:\export\expr\jni\hello\gen > > javaSrcComp: > [javac] Compiling 2 source files to C:\export\expr\jni\hello\bin > > ctags: > > javaComp: > > javah: > [echo] building *_jni.h... > > ccComp: > [mkdir] Created dir: C:\export\expr\jni\hello\ctmp > [copy] Copying 2 files to C:\export\expr\jni\hello\ctmp > > [echo] Compiler Name: g++ > [echo] Compiler Version: > [exec] g++ (GCC) 3.2 20020927 (prerelease) > [exec] Copyright (C) 2002 Free Software Foundation, Inc. > [exec] This is free software; see the source for copying conditions. There is NO > [exec] warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. > > > [echo] Compiling for Cygwin... > [echo] Linking for Cygwin... > [delete] Deleting directory C:\export\expr\jni\hello\ctmp > > build: > > go: > [java] loading library > [java] calling sayHello > [java] Hello World from C! > [java] trying to get array > [java] answerArrayObj=0x8b74cc > [java] trying to get elem[0] > [java] elem0=0x8b74d0 > [java] elemClass=0x8b74d4 > [java] valueFieldID=0x22 > [java] trying to get valueObj > [java] valueObj=0x8b74d8 > [java] trying to get string chars > [java] initial string = 'initial value from java' > [java] trying to set string chars > [java] newJString=0x8b74dc > [java] getting constructor MID > [java] msgCID=0x8bbf18 > [java] calling constructor > [java] trying to set string chars > [java] newJString2=0x8b74e4 > [java] setting newElem value > [java] trying to set elem[1] > [java] sayHello() returning > [java] sayHello done > [java] answer[ 0 ] = 'Hello World from C!' > [java] answer[ 1 ] = 'the new C string value' > [java] answer[ 2 ] = 'initial value from java' > > clean: > [delete] Deleting directory C:\export\expr\jni\hello\bin > [delete] Deleting directory C:\export\expr\jni\hello\gen > > BUILD SUCCESSFUL > Total time: 9 seconds > > > > > > > cd expr/jni/invoke > ant > > Buildfile: build.xml > > clean: > > init: > [mkdir] Created dir: C:\export\expr\jni\invoke\bin > > javaComp: > [javac] Compiling 1 source file to C:\export\expr\jni\invoke\bin > > ccCygwin: > [echo] Compiling C++ for Cygwin > > dlltoolCygwin: > > > ccCompCygwin: > > [echo] Compiler Name: g++ > [echo] Compiler Version: > [exec] g++ (GCC) 3.2 20020927 (prerelease) > [exec] Copyright (C) 2002 Free Software Foundation, Inc. > [exec] This is free software; see the source for copying conditions. There is NO > [exec] warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. > > > > ccSun: > > ccComp: > > build: > > go: > > goCygwin: > [exec] <C++> program starting > [exec] <java> Hello World from C! > [exec] <C++> program terminating > > goSun: > > clean: > [delete] Deleting directory C:\export\expr\jni\invoke\bin > > BUILD SUCCESSFUL > Total time: 12 seconds > > > At 02:12 PM 5/20/2003 +0800, Shaddy Baddah wrote: > > >I am having exactly the same problem trying to build Java JNI's under Cygwin > >(actually, they are the examples from the 'GNU Win32 related projects' > >page ). Robert Bercik, did discover a fix for the problem you encountered? > > > >I have more weirdness to describe. I can run the Java app that loads in the > >JNI under a regular Windows 2000 'cmd' window and it works fine, regardless > >of whether there is a cygwin1.dll active or not. But if I try and run the > >same Java app from within a cygwin shell, it crashes in the same way. There > >must be a simple explanation/fix to this one. Help would be greatly > >appreciated. > > > >Thanks in advance, > >Shaddy > > > -- Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple Problem reports: http://cygwin.com/problems.html Documentation: http://cygwin.com/docs.html FAQ: http://cygwin.com/faq/
