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<p class="MsoNormal"><span lang="EN-US">Hi,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> When I changed code as following:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">public class Connect {<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> // Load the native part<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> static {<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> Libvirt.INSTANCE.virInitialize();<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> try {<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> ErrorHandler.processError(Libvirt.INSTANCE);<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> } catch (Exception e) {<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> e.printStackTrace();<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> }<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> <o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> + Libvirt.INSTANCE.virSetErrorFunc(null, new ErrorCallback());<o:p></o:p></span></p>
<p class="MsoNormal" style="text-indent:21.6pt"><span lang="EN-US">}<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">The server will generate the following core dump:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Program terminated with signal 6, Aborted.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">#0 0x0000003f9b030265 in raise () from /lib64/libc.so.6<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">(gdb) where<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">#0 0x0000003f9b030265 in raise () from /lib64/libc.so.6<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">#1 0x0000003f9b031d10 in abort () from /lib64/libc.so.6<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">#2 0x0000003f9b06a84b in __libc_message () from /lib64/libc.so.6<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">#3 0x0000003f9b07230f in _int_free () from /lib64/libc.so.6<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">#4 0x0000003f9b07276b in free () from /lib64/libc.so.6<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">#5 0x00002aaaacf46868 in ?? ()<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">#6 0x0000000000000000 in ?? ()<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">The problem was caused that when JNA call setErrorFunc, it will create ErrorCallback object. But when GC is executed, the object is GCed. But even I change code as following.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">When GC is excuted, the callback object will be moved. Then C can’t find this object. Both of scenarios will cause core dump. It seems that JNA mustn’t provide ErrorCallback Class,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Because nobody can use this. <o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Please correct me.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">public class Connect {<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> + private static final ErrorCallback callback = new ErrorCallback();<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> // Load the native part<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> static {<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> Libvirt.INSTANCE.virInitialize();<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> try {<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> ErrorHandler.processError(Libvirt.INSTANCE);<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> } catch (Exception e) {<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> e.printStackTrace();<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> }<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> <o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> + Libvirt.INSTANCE.virSetErrorFunc(null, callback);<o:p></o:p></span></p>
<p class="MsoNormal" style="text-indent:21.6pt"><span lang="EN-US">}<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">B.R.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Benjamin Wang<o:p></o:p></span></p>
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