Thanks for your answers:
You can set a primary search path at compile/link time with -R or -rpath.
When I launch my app on Ubuntu 14.04: it doesn't find libsfml-graphics.so.2.3 because it doesn't exist (only version 2.1 exist). Do you suggest I insert SFML 2.3 directly on my package and I reference it with -rpath option ?
Running ldd -v on a file will list its dependencies.
Yes, I have already run this command and the dependencies returned are libsfml-graphics2.3v5,.... But as I explain in my first post: it's incompatible with Ubuntu older version like 14.04
Here others questions which could help me to understand better:
* If I create an binary using SFML 2.3. Could I execute it with SFML 2.1 without re-compile it ?
* Why in Ubuntu 14.04, the package name is "libsfml-graphics2" (which refer to version 2.1) and on Unbutu 15.10, the package name is "libsfml-graphics2.3v5". Shouldn't we have same package name: "libsfml-graphics2" ?