This repository is abandoned. The new reposity is at https://github.com/noahdossan/pyunix
PYunix (pico unix) is a tiny kernel/microkernel simulation program with a functional terminal and multiple kernel system calls. It mimics and is basically a very oversimplifed version of the Linux kernel, that you can run as one program itself.
You can build with a C/C++ compiler such as GCC or MinGW, or download and run the already compiled executables.
This has been tested to run on Windows and Linux. Unix compilers such as GCC or MinGW only work because of headers only in Unix (unistd.h).
It is possible to run this on Android since there are some C/C++ IDEs for Android.
Contributions to PYUNIX are very welcome. I am a beginner so help is appreciated.
A lot of the features are .h files in their respective directories. To add or modify a kernel feature/call update the kernel/setup.h file.
Running help in the terminal shows available commands. Updated as of 0.3.1
allocate <process> <size> - Allocate memory to a process
free <process> - Free memory from a process
start <process> <size> - Start a new process with specified memory
ps - List all processes that are currently running
kill <process> - Kill a running process
echo <string> - Repeat text with specified string
reboot - Reboot the system
exit - Exit the terminal and shut down the system
These are the various system calls you can use to interact with the mini PYUNIX kernel. Updated as of 0.3.0
void kernel_init();
void kernel_start();
void kernel_switch_to_real_root_filesystem();
void kernel_shutdown(bool reset);
void kernel_panic(const char* reason);
void kernel_oops(const char* reason);
void initramfs_load();
void init_system_start();
void init_system_create_startup_processes();
void process_manager_create_process(const char* name);
void process_manager_schedule();
void process_run(const char* name);
void process_wait(const char* name);
void process_allocate_memory(const char* name, int size);
void process_deallocate_memory(const char* name);
void memory_manager_allocate(const char* name, int size);
void memory_manager_free(const char* name);
void device_initialize(const char* name);
void device_manager_add_device(const char* name);
void device_manager_list_devices();
void clear_scr();
The terminal_kill_process() call includes a is_kernel attribute. Attempting to kill a system process such as init initiates a kernel panic.
However, if is_kernel is set to true, the system process protection is overrided.
kernel_init(): This call is ran before the kernel is started. It does nothing, but you can put code to run there before the kernel is started.
kernel_start(): Initializes the kernel.
kernel_switch_to_real_root_file_system(): Switches from initramfs to root file system.
kernel_shutdown(): Kills init and shuts down system. (TO-DO: kill all running processes).
kernel_panic(reason): Initiates a kernel panic.
kernel_oops(reason): Initiates a kernel oops.