How to write self-modifying code in x86 assembly

Question

I\'m looking at writing a JIT compiler for a hobby virtual machine I\'ve been working on recently. I know a bit of assembly, (I\'m mainly a C programmer. I can read most ass

Answer 1

I've never written self-modifying code, although I have a basic understanding about how it works. Basically you write on memory the instructions you want to execute then jump there. The processor interpret those bytes you've written an instructions and (tries) to execute them. For example, viruses and anti-copy programs may use this technique.
Regarding the system calls, you were right, arguments are passed via registers. For a reference of linux system calls and their argument just check here.