[Please keep replies on the mailing list so that others can benefit from following the discussion] On Fri, Oct 06, 2017 at 06:04:46AM +0000, emlyn.jose@wipro.com wrote:

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qemu is a hypervisor, qemu-img is a program for manipulating disk images. They are very different things, and it makes no sense to substitute qemu-img for qemu.

I do not want to substitute qemu-img instead of qemu :

• virt-resize uses qemu-kvm as well as qemu-img.

• My qemu binaries come from a different path(instead of /usr/bin/) which is set in $PATH already

• Providing "export PATH=/path/to/qemu-kvm/and/qemu-img" (both binaries are in same location) and using "--with qemu=qemu-kvm qemu-img" takes only the qemu-kvm correctly

Don't use ‘--with-qemu=...qemu-img’, it is simply wrong. The --with-qemu parameter is intended to specify the hypervisor, and qemu-img is not a hypervisor.

but qemu-img is still not taken from the $PATH. Why?

qemu-img comes from the PATH, see: https://github.com/libguestfs/libguestfs/blob/master/lib/create.c#L317 https://github.com/libguestfs/libguestfs/blob/master/lib/info.c#L194 External commands run through the guestfs_int_cmd_* mechanism can be displayed by enabling debugging: http://libguestfs.org/guestfs-faq.1.html#debugging-libguestfs so I suggest you enable this to see exactly what's going on.

• I used "--with qemu=qemu-kvm qemu-img" as well as “export LIBGUESTFS_HV=/path/to/qemu-img” which will obviously override qemu-kvm to qemu-img

Hope you got what I am saying now?

I do not want to substitute qemu-img instead of qemu-kvm. Both has to be taken from the specified path i.e., $PATH.

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P.S: Its surprising to see that even after uninstalling the available qemu-img package from my host, libguestfs takes it without any issues!! Where does it take that "qemu-img" binary from?

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From $PATH.

How is that possible when there is no qemu-img installed which in turn has no such binary available in $PATH. That is weird!!! I just want to know if libguestfs itself has some qemu-img binary inbuilt to use it for virt-resize.

You just said above that you set the PATH to contain both qemu-kvm and qemu-img. Anyway, I suggest you enable debugging which will show you exactly what libguestfs is doing. Also don't put qemu-img into the ‘./configure --with-qemu’ parameter. Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones Read my programming and virtualization blog: http://rwmj.wordpress.com virt-df lists disk usage of guests without needing to install any software inside the virtual machine. Supports Linux and Windows. http://people.redhat.com/~rjones/virt-df/