RTLinux

RTLinux is a real-time operating system that was developed for industrial control and embedded systems. It is a hard real-time operating system, meaning that it can guarantee that tasks will be completed within a specific deadline. This makes it suitable for applications where timing is critical, such as in robotics, aerospace, and medical devices.

RTLinux was originally developed by FSF Europe and was based on the Linux kernel. It was designed to be a preemptive, priority-based multitasking operating system. The RTLinux kernel was a separate kernel that ran in parallel with the standard Linux kernel. This allowed for a high degree of determinism while still leveraging the extensive capabilities of Linux for non-real-time tasks.

RTLinux was known for its performance and reliability. It was widely used in a variety of industries, and its success contributed to the growing adoption of Linux in embedded and real-time applications. Over time, advancements in the main Linux kernel, particularly through projects like PREEMPT_RT, have addressed many of the real-time requirements that RTLinux initially specialized in, leading to a gradual integration of these capabilities directly into the mainline Linux kernel. While dedicated RTLinux distributions may be less common now, its legacy lies in pushing the boundaries of real-time performance for Linux-based systems.