Detailed Introduction#
L4Re is an operating system and a hypervisor as it runs both L4Re applications and virtual machines.
It is built on a small kernel – a microkernel – and a user-level infrastructure composed out of small components with distinct functions (see services). Please refer to Architecture Concepts to learn about the underlying concepts.
We call it L4Re Operating System Framework as it provides the building blocks to construct tailored systems for specific use-cases.
The L4Re Operating System Framework:
supports many hardware platforms,
runs on Arm, MIPS, RISC-V, and x86 architectures
is open-source software
The functionality features:
A C library with pthreads support and shared libraries
libstdc++, fully-featured C++ standard library
C, C++, Ada and Rust (work in progress) environments
Client/Server and communication frameworks
Virtual file-system infrastructure
Drivers, such as UART, NVMe, AHCI, network
Scriptable program and system management using Lua
Virtual machines and Hypervisor
Platform and device management, including ACPI, PCIe, device tree
Input/output multiplexing, including graphics
L4Re’s Buildsystem utilises GNU Make to provide high customizability for the user when it comes to choosing compilers and target platforms to cross-compile for.