At 08:23 AM 6/16/2004, you wrote: >I have been attempting to port a large program from >Linux to Windows using Cygwin. The program is written >in Java, C and C++; using the JNI to link them >together. > >I have successfully compiled and linked all of the C >and C++ code using Cygwin, and successfully executed a >test program written in C++. > >The following illustrates the compiler flags I was >using: > >g++ -c -D__int64="long long" ###includes### *.cc >gcc -Wl,--add-stdcall -shared -o ~/prism/lib/file.dll >*.o -L ~/prism/lib -lutil -lepd > >The problem comes when the JNI tries to load the >shared dlls in the loadLibrary() method. The JNI >appears to be able to find the libraries, as no >UnsatisfiedLinkError is reported; however, the >execution halts, giving no output. > >It appears that JNI has problems with cygwin1.dll, >because I have had no JNI problems with dlls not >created using Cygwin. > >After searching the Internet and this mailing list, >most sources seem to point out that I should use the >-mno-cygwin compiler flag. This appears to remove the >need for the cygwin1.dll at runtime. However, this >results in compile errors. For example: > >$ gcc -c -D__int64="long long" -I../mnemosyne/ *.c > >This works fine … but this doesn’t: > >$ gcc -mno-cygwin -c -D__int64="long long" >-I../mnemosyne/ *.c >datalimit.c:17:26: sys/resource.h: No such file or >directory >pipefork.c:12:22: sys/wait.h: No such file or >directory
<snip> >I have searched the Internet, the Cygwin manual and >Cygwin’s FAQ and I have found nothing that explains >the problem with JNI and cygwin1.dll. Could anyone >either point me in the right direction or say whether >I am doing anything wrong. Or does anyone know if >there is a way to make this work without the need for >the cygwin1.dll? Your C/C++ code seems to assume a POSIX environment. You don't get that from Windows. So you'll need to compile your C/C++ code *without* '-mno-cygwin' if you don't want to do some porting. I know very little about Java but I'm assuming you're trying to load the C/C++ DLLs you make with JNI. If that's true and you want to try to avoid porting, you might find this link interesting <http://sources.redhat.com/ml/cygwin/2004-06/msg00274.html>. Basically, cygwin1.dll won't be properly initialized if it's loaded from a non-Cygwin program. So you'll need to try a little wizardry to make this work. Or you could submit a patch to make this work for everyone using other magic. ;-) -- Larry Hall http://www.rfk.com RFK Partners, Inc. (508) 893-9779 - RFK Office 838 Washington Street (508) 893-9889 - FAX Holliston, MA 01746 -- 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/
