LIEF

You can use `xxd` from the vim package to generate these. You'll find out pretty quickly that this is only suitable for small resources: gcc and clang blow up in both time and space on very large literal arrays. If you need to ship more than a few megabytes, find a different technique. I used this technique for awhile, but it was too problematic for my use case. Now, I use https://github.com/lief-project/LIEF -- among other things, this project can modify Windows PE, macOS Mach-O, and Linux ELF binaries to add resources to them, then offers an API to read them back later. It's a little different for each format, but it's capable of doing all three and I was able to build a cross-platform resource-bundling system that doesn't care how big the resources are.

My team is working on this problem in the context of creating Node.js single-executable applications. While the naive approach of just appending data at the end of the binary works, it is not friendly with code-signature in macOS and Windows given that signing operates on PE and Mach-O sections. We have recently open-sourced a small tool called Postject (https://github.com/postmanlabs/postject), which is able to inject arbitrary data as proper ELF/Mach-O/PE sections for all major operating systems (with AIX support coming). The tool also provides C/C++ cross-platform headers for easily traversing the final binary and introspect whether the segment is present or not. The tool is based on the LIEF (https://github.com/lief-project/LIEF) project. At Postman, we are making use of this on our custom Node.js single-executable applications and so

Nice write-up! FWIW, there's a bunch of other interesting tools for ELF, https://github.com/MattPD/cpplinks/blob/master/executables.m... LIEF (Library to Instrument Executable Formats, https://github.com/lief-project/LIEF, an interesting project on its own) also has good references, https://lief.quarkslab.com/doc/latest/references.html