A Quine clock in C inspired by Tsoding's Quine clock in C adventure (https://www.youtube.com/watch?v=plFwBqBYpcY) and viewer codecat69's inline asm include trick (at 3:14:40), which allows the source code to be smaller in size while still allowing renaming (as opposed to reading the file at runtime). It is unfortunately still not as small as the JS Quine clock by Martin Kleppe @aemkei on X.
Simply clone the repository and (if you have gcc installed and added to path) run 'make'. In the case of another compiler: set it in the Makefile at the top and try again (you might need to change some compiler-specific flags).