yum for custom package management on my embedded linux system

Hi,

I would like to use yum on my custom embedded linux system. The Linux
distro has been put together by yocto build system.


In my custom rpm packages I have provided a special string, say
"[12abc]" in the package summary and I can search for packages using:
yum search "[12abc]"

But the above command lists all the packages: installed + not
installed. How Can list only my packages that are installed? & the
ones that are not installed?


Any inputs will be of help to me.


Regards, Pj