tosi-mosi

The only proper way to debug 16-bit code on Qemu+GDB

(or nearly so...)

GDB is undeniably an extremely versatile debugger, with the ability to add breakpoints, watchpoints, dump memory, registers, and the source code (along with its corresponding assembly). These features make it the perfect Swiss Army knife for most programmers. In addition to that, the possibility of implementing a 'GDB Stub' and automatically supporting GDB in your application makes it an almost universal debugger for a variety of tasks.

Qemu, like other virtual machines (such as 86Box), also implements debugging via GDB Stub, which enormously facilitates the development of bootloaders, operating systems, and more. The support for 32-bit and 64-bit code is quite good, and I have never seen any complaints about it. However, for 16-bit/real mode...

Is debugging in 16-bit/real mode really that bad?

If you have ever tried to debug 16-bit code on Qemu, you know how painful it can be:

GDB thinks your code is

Warning

This is a tutorial from 2016, originally for installing debian jessie, it may work for newer versions of debian, but I haven't check it (however, it should mostly work because not that much changed since then). You may want to change every occurrence of buster to a name of a new version of debian.

Install debootstrap

Make work directory:

mkdir work
cd work

Effective Modern CMake

Getting Started

For a brief user-level introduction to CMake, watch C++ Weekly, Episode 78, Intro to CMake by Jason Turner. LLVM’s CMake Primer provides a good high-level introduction to the CMake syntax. Go read it now.

After that, watch Mathieu Ropert’s CppCon 2017 talk Using Modern CMake Patterns to Enforce a Good Modular Design (slides). It provides a thorough explanation of what modern CMake is and why it is so much better than “old school” CMake. The modular design ideas in this talk are based on the book [Large-Scale C++ Software Design](https://www.amazon.de/Large-Scale-Soft

Instructions how to install Debian using debootstrap. Below instructions were verified to work with debootstrapping Debian 11.

Sublime Text 3 - Useful Shortcuts (Windows)

General

Shortcut	Description
`Ctrl`+`Shift`+`P`	command prompt
`Ctrl`+`Alt`+`P`	switch project
`Ctrl`+`P`	go to file
`Ctrl`+`G`	go to line

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