Finite State Machine Labs, Inc.: FSMLabs - Makes dual kernel RTLinux and RTCore/BSD, and OpenRTLinux RTOSs, realtime networking, protected memory, XML/RPC controls, embedded Linux developer kit; has RT developer tutorials and white papers; second tier support for Linux product vendors; software development, consulting (embedded, cluster, SMP).
LinuxDevices.com: KURT: The KU Real-Time Linux - KURT introduction and analysis.
Team Takes Different Path to Real-time Linux - RTLinux doesn't try to change Linux into an RTOS, it instead provides a new RT kernel incorporating Linux as a low-priority thread, so the RTOS stays small, streamlined and keeps Linux as a base for common applications. [EE Times]
Linux, Real-Time Linux, & IPC - When dealing with realtime systems, IPC overhead becomes important; examines two of the best IPC mechanisms available for Linux: FIFO, shared memory. [Dr. Dobb's Journal]
KURT: KU Real Time Linux - by University of Kansas (KU) Center for Research, Inc. Between a hard and soft real-time OS.
RTLinux - Growing article, with links to many related topics. Wikipedia.
RTLinux Free - Portal for free version of RTLinux; news, FAQs, search, Forum, downloads, FSMLabs contact; OCERA.
OCERA - Open Components for Embedded Real-time Applications: integrated execution environment for embedded realtime programs. Combines 2 kernels, Linux and RTLinux-GPL to support critical tasks (RTLinux-GPL executive) and soft realtime programs (Linux kernel).
RTAI - RealTime Application Interface for Linux: realtime extension allows writing programs with strict timing constraints for Linux. Supports ARM, PowerPC, x86 32/64.
RTAI - Growing article, with links to many related topics. Wikipedia.
DIAPM RTAI - Original home of RTAI, news archive, documents, programs, links, team, downloads, mail list, bug reports.
RTAI.dk - Wiki for DIAPM RTAI RealTime extension to Linux; much information, instructions, tips, success stories, related projects, links, bootable CDs.
RTLinux-gpl FTP Repository - FTP and mail list archives, anonymous CVS access.
Xenomai - Hard realtime development framework, works with Linux kernel; pervasive, interface-agnostic, support to programs, seamlessly integrates with GNU/Linux environment; based on abstract RTOS core, build any kind of realtime interfaces, over nucleus which exports set of generic RTOS services.
REACT for Linux - Hard realtime extension, under 30µs interrupt response times; originally standard with SGI IRIX Unix OS; Silicon Graphics, Inc. Open source.
Xenomai - Wiki for realtime Linux framework: news, information, instructions, tips, success stories, roadmap, links.