Is there a Linux equivalent of Windows' "resource files"?

Question

I have a C library, which I build as a shared object for Linux and a DLL for Windows with MinGW32. The API depends on a couple of data files (statistical models) which I'd really like to roll in with the SO/DLL so that deployment is just one file.

It looks like I can achieve this for Windows with a "resource file" compiled with windres, but then I've got to write a bunch of resource-handling code for Windows, and I'm still stuck with the files on Linux.

Is there a way to achieve the same functionality on Linux?

Even better, is there a portable solution?

Answer 1

Nothing so automatic as Windows resource files. I can offer two options:

1. Declare it as file-scope variables in C. That's traditional. A Big Array Of Ints.

2. Learn about the wonders of ld control files, see the GNU ld documentation.

Answer 2

Two potential solutions:

• Phong Vo's sfio library, which is part of the AT&T Advanced Software Technology toolset, is a wonderful replacement for C stdio.h, and it will allow you to open either files or memory blocks using a single API. So you can easily convert your existing files to C initialized data to include in your DLL or SO file.

  This is a good cross-platform solution, but the penalty is that the learning curve to get started is pretty high. They don't make it easy to figure out how stuff works or to take one part of their toolset and split it out for use independent of the other parts. But the good news is that if you want to adopt their U/Win system for running Unix codes on windows (all part of the same toolset), you can create DLLs and SOs using the same system.

• For this kind of problem I often fall back on Lua; I can stored Lua data either in external files or within C as initialized data. This is great for distributing everything in one .so file; I do this for my students.

  Again the downside is that you have to master and incorporate a new technology.

In my own work I use Lua over the AT&T stuff for these reasons:

• Lua has a much smaller footprint and is designed to play well with others; with AST you really have do adopt their way of doing things.

• The learning curve with Lua is much less steep; you can be productive very quickly.

• Lua is dead easy to install and it's easy to get information about it. AST has its own quirky installation process shared by nobody else in the world; it's often hard to make the installation work; and it's harder to get information about it.

• Using Lua has a lot of other payoffs, so the effort spent learning Lua and learning how to incorporate Lua into C codes is easy to amortize over multiple projects.

Answer 3

It's actually quite simple on Linux and other ELF systems: http://www.linuxjournal.com/content/embedding-file-executable-aka-hello-world-version-5967

OS X has bundles, so you just build your library as a framework and put the file in the bundle.