Difference between revisions of "Linux"
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== Sound == | == Sound == | ||
− | + | It is possible to output digital audio by binding the the aplay command into your intro. | |
+ | APLAY is available on most of the Linux distributions and can be tested by running: | ||
+ | |||
+ | $ aplay -c8 /dev/urandom | ||
+ | |||
==== Make some noise ==== | ==== Make some noise ==== |
Revision as of 05:49, 8 August 2021
Contents
Introduction
For X86 related information, please check the main pages on this website, as a lot of the same tricks will also work with X86 linux sizecoding. This page goes into the specifics of getting small binaries on linux.
Linux system
This section of the sizecoding.org wiki targets 32-bit X86 based Linux binaries (ELF format).
Setting up
Setting up your development platform for Linux development:
- Suggested Distributions : Any X86-based Linux distribution that allows for execution of 32-bit executables.
- Assembler: NASM
Furthermore, it is important that the user has access to the dev/fbo framebuffer. This can be achieved by launching a virtual (fullscreen) console using CTRL-F3/F4 in most distributions, login and making sure the user has access to the video group. If this is not the case for some reason, you can add your user to the videogroup like so:
sudo usermod -a -G video username
ELF Header Information
To be added.
System Calls
Interaction with the Linux OS is mostly done via int 0x80 system calls. This usually includes dealing with opening files/framebuffer/audio and handling timers.
A full list of system calls and their expected register arguments is available at: https://syscalls32.paolostivanin.com/
Self compilation
To be added.
Accessing video
Accessing video
Getting something on screen
To be added soon.
Sound
It is possible to output digital audio by binding the the aplay command into your intro. APLAY is available on most of the Linux distributions and can be tested by running:
$ aplay -c8 /dev/urandom
Make some noise
To be added soon.