java.lang.UnsatisfiedLinkError in Linux

Question

I've managed to get into a linux machine to try the HotKey library suggested in this answer.

I've compiled the sample code and now I run the program and I've got the following message:

[oracle@machine jxgrabkey-0.2.1_i386]$ java -classpath lib/JXGrabKey.jar:Example JXGrabKeyTest

Exception in thread "main" **java.lang.UnsatisfiedLinkError:** /home/oracle/javasample/jxgrabkey-0.2.1_i386/lib/libJXGrabKey.so: /usr/lib/libstdc++.so.6: version `GLIBCXX_3.4.9' not found (required by /home/oracle/javasample/jxgrabkey-0.2.1_i386/lib/libJXGrabKey.so)
   at java.lang.Runtime._load(libgcj.so.7rh)
   at java.lang.Runtime.load(libgcj.so.7rh)
   at java.lang.System.load(libgcj.so.7rh)
   at JXGrabKeyTest.main(JXGrabKeyTest.java:17)

I know how to handle this in Windows ( just by adding the DLL to the PATH env var ) but I'm not that sure about linux.

I've read something about LD_LIBRARY_PATH and some other env vars but I can make it work.

Any advice?

EDIT

After the support from mmyers to indentify the problem and reading this thread and this other .

I can tell:

My system is: Linux 2.6.18-53.el5

My GCC version(s) is ( are) :

gcc-c++-4.1.2-14.el5

gcc-gfortran-4.1.2-14.el5

libgcc-4.1.2-14.el5

gcc-4.1.2-14.el5

The problems is I require gcc 4.2.0

Aaand apparently there is no gcc 4.2.0 for my system.

I guess I would have to wait for it to come or the author recompile it in a previous version.

mmyers, thanks a lot for your help.

Answer 1

Did you try -Djava.library.path=/path/to/library ?

EDIT: Re-reading the error message, it looks to me that the native library you're loading is trying to link to glibc version 3.4.9, which apparently is not installed. Can you check what version of glibc you have? What Linux distro are you running?

EDIT2: The problem seems to be narrowed down to libstdc++. I'm about to the edge of my knowledge, but this thread might be useful. It suggests upgrading to gcc 4.2; from the comments, you appear to have version 4.1.2. Let me know if that doesn't work.

Answer 2

subes, JXGrabKey dev here ...

I don't know much about this error myself, but your lead about gcc and/or libstdc++ should be right

Personally I am using the gcc version shipped with Ubuntu 8.10 atm. I always stick to the latest version shipped.

Current version: g++ (Ubuntu 4.3.2-1ubuntu12) 4.3.2

The following libstdc++ packages are installed on my machine: http://packages.ubuntu.com/intrepid/libstdc++5 http://packages.ubuntu.com/intrepid/libstdc++6

Hope this helps, if you find anything useful, tell me. :) Maybe i have to compile jxgrabkey with an older version of gcc for releases, so it is downwards compatible? Does anyone have a wise advice? ^^