将共享库与linux中的另一个共享库链接在一起

I am trying to build a shared library. Let us say libabc.so .It uses another .so file , say lib123.so (a lib in /usr/local/lib) .Now i am using my shared lib libabc.so in my application. say my-app.I want to know how i should link these binaries??i don't want to link my-app with lib123.so directly. my-app should be linked with only libabc.so. How can i do this?I am trying to build a shared library. Let us s