You must extract the root filesystem if you want to boot the image using NFS or you want to use the root filesystem as the target sysroot. For example, the Eclipse IDE environment with the Eclipse Yocto Plug-in installed allows you to use QEMU to boot under NFS. Another example is if you want to develop your target application using the root filesystem as the target sysroot.
To extract the root filesystem, first source
the cross-development environment setup script and then
use the runqemu-extract-sdk
command on the
filesystem image.
For example, the following commands set up the environment and then extract
the root filesystem from a previously built filesystem image tarball named
core-image-sato-sdk-qemux86-2011091411831.rootfs.tar.bz2
.
The example extracts the root filesystem into the $HOME/qemux86-sato
directory:
$ source $HOME/toolchain_dir/environment-setup-i586-poky-linux $ runqemu-extract-sdk \ ~Downloads/core-image-sato-sdk-qemux86-2011091411831.rootfs.tar.bz2 \ $HOME/qemux86-sato
In this case, you could now point to the target sysroot at
$HOME/qemux86-sato
.