Hi Rosy
The generation of libydk.a is controlled by the file CMakeList.txt. Please note that the build includes also compilation of libnetconf and libyang objects, which are then included to the libydk.a.
If you succeed to build libydk.so/libydk.dylib, please share your code with YDK community. Also please explore build of samples and unit tests using dynamic link library.
Yan Gorelik
YDK Solutions