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</o:shapelayout></xml><![endif]--></head><body lang=ZH-CN link=blue vlink=purple style='text-justify-trim:punctuation'><div class=WordSection1><p class=MsoNormal><span lang=EN-US>Hi,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> Excuse me, I have a question when I reading the libvirt source codes.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> I have known the process of how libvirt start/manage qemu, since I need to write a driver based on libvirt. But one thing also confused, please give me some tips.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> 1.<o:p></o:p></span></p><p class=MsoNormal style='text-indent:21.0pt'><span lang=EN-US>In qemu_command.c, there is a function call “cmd = virCommandNewArgList(emulator, "-S", NULL);”, which initializes pointer “cmd”. However, I don’t find the initial value of “cmd->args”, which represents the input of </span><span lang=EN-US style='font-size:12.0pt;font-family:"Times New Roman","serif"'>virFindFileInPath</span><span lang=EN-US> in Util.c. Through </span><span lang=EN-US style='font-size:12.0pt;font-family:"Times New Roman","serif"'>virFindFileInPath, one could find </span><span lang=EN-US>a requested executable file in the PATH env to start specified hypervisors. <o:p></o:p></span></p><p class=MsoNormal style='text-indent:21.0pt'><span lang=EN-US>So could you please tell me what the value of args[0] is? Or where does cmd->args initialize?<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> 2.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> In qemu_driver.c, there is a function call “vm = virDomainFindByUUID(&driver->domains, dom->uuid);”, whose returned value “vm” is important in the next functions. Then we could get the “vm”’s value in hash.c which is the end part to lookup domains saved in hashtable. <o:p></o:p></span></p><p class=MsoNormal style='text-indent:21.0pt'><span lang=EN-US>May I know where does HashTable initialize? I mean where can I set the hashtable’s values in detail, if I want to modify some values?<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> 3.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> This might be the same as question 1.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> In command.c, “execve(cmd->args[0], cmd->args, cmd->env)” is a way to exec command. About qemu_driver, what is the value of those three inputs? <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> Thanks a lot!<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> Regard,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> Corey<o:p></o:p></span></p></div></body></html>