I'm a PC tech, mainly hardware work, and have been tinkering around with programming since qbasic (never learned C++ though). I have a solid knowledge of computers and hardware, yet I've never gotten into the scene of console modding. I've used the mods plenty, but never actually contributed. Now, I'm thinking about trying to expand my knowledge in to console realm, and need some explaining.
When the jailbreak runs, I understand that it exploits a piece of code in the bootup of the system, most likely with a buffer overflow, and allows unsigned code to run, then it inserts a few commands (syscalls) that are not normally found in the system. I can imagine that its only modified in run time memory, or else the JB wouldn't need to run each time. I could assume that much since the launch of the first dongle, but what surprises me is thats about all I can find online. My question is, how exactly is the system modified? What specific files are modified, and in what way?