library location for project

Question

I have started an C++ SFML project for linux. I was wondering where the .so's should go. Should they go inside the project folder so a user can simply run the program after they get it? Or should the user have the SFML library installed on there linux machine before they run my program?

Answer 1

At the distribution level SFML will be a dependency, i.e. a user will have to install it (or their package manager will have to install it) before compiling your program. If a user wants to compile it, they will also need the header files (often there's a separate "devel" package to install). You shouldn't have to distribute the .so files, and it's probably better (for everybody) if you don't.

You will need to check if the user has it, e.g. using autoconf you need to check for the relevant headers in your configure.ac for the application project. For example, to check for the math library, because I'm using the exp() function, I'll use

AC_CHECK_LIB([m], [exp])

to create a check during the configure step. Luckily autoscan can check this for you and create a skeleton configure.ac file called configure.scan. See also Cmake.

HTH.

Answer 2

You should make your program depend on the specific library (and version) that it needs. If you're planning to package it into an rpm/deb file you should add the dependency there too so that it can be checked and applied by package managers (e.g. apt can install all the dependency packages of a given package)

Answer 3

Even if you did include the .so files, you have no guarantee that the user will be able to run it (different architecture, libraries linked against different libc, ...). Either link statically, or better yet, just let them provide the supporting libraries themselves.

@Joel J. Adamson's answer to use autoconf is a good idea. SFML doesn't come with a pkg-config file, so you will check for SFML as follows:

dnl Checking for a C++ compiler
AC_PROG_CXX

dnl Checking C++ features. This tells configure to use the C++ compiler for checks.
AC_LANG_PUSH([C++])
dnl Check for a SFML header.
AC_CHECK_HEADER([SFML/Config.hpp], [], [AC_MSG_ERROR([SFML headers not found.])])
AC_LANG_POP([C++])

Checking for the libraries is a bit more difficult because of name mangling and so on. Tyler McHenry wrote a good article on this part, if you want to be thorough.