Hi Eric, Thanks for the comments. Could you please help review the next version? Best Regards, Olivia > -----Original Message----- > From: Eric Blake [mailto:eblake@xxxxxxxxxx] > Sent: Thursday, February 28, 2013 1:02 AM > Cc: Yin Olivia-R63875; libvir-list@xxxxxxxxxx > Subject: Re: [PATCH v3 2/4] qemu: add dtb capability > > On 02/27/2013 09:56 AM, Eric Blake wrote: > > >> @@ -944,6 +945,8 @@ virQEMUCapsComputeCmdFlags(const char *help, > >> } > >> if (strstr(help, "-uuid")) > >> virQEMUCapsSet(qemuCaps, QEMU_CAPS_UUID); > >> + if (strstr(help, "-dtb")) > >> + virQEMUCapsSet(qemuCaps, QEMU_CAPS_DTB); > > > > This won't work. -dtb did not exist prior to qemu 1.2, and for all > > qemu newer than 1.2, we do NOT scrape '-help' output; instead, we use > > QMP query commands. You need to figure out the corresponding QMP > > command that we can use to tell when dtb support exists in qemu. > > I stand (slightly) corrected: it looks like -dtb was added in qemu 1.1 > (qemu commit 379b5c7), which means we DO need -help scraping for that > version of qemu. Then, since it predates when QMP queries are reliable, > you can get away with blindly setting QEMU_CAPS_DTB when targetting a qemu > new enough to support QMP queries without actually having to query for it. > But it's still something to be fixed before this patch is ready :) > > -- > Eric Blake eblake redhat com +1-919-301-3266 > Libvirt virtualization library http://libvirt.org -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list