Indeed, and some of the things in this article are blatantly wrong, such as using an "invalid instruction" to cause a signal we can catch. Debuggers do NOT use

Indeed, and some of the things in this article are blatantly wrong, such as using an "invalid instruction" to cause a signal we can catch. Debuggers do NOT use invalid instructions, on x86 and AMD64 they use 0xCC (INT 0x03) on other platforms they use whatever dedicated trap-to-debugger instruction there may be, there's not usually a need to use an invalid instruction to do debugging.