Lexicon Entry
OS Subsystem
In the context of the NT Kernel, a subsystem (like the Win32 subsystem or the older POSIX subsystem) is a user-mode server process that exposes specific OS behaviors and APIs, translating them into native NT system calls.
Related Knowledge & Cross-References
Guide
The NT Kernel Approach: Understanding Windows Process Creation
A deep dive into the NT Kernel approach to processes. Learn why Windows lacks fork(), the architecture of Windows subsystems like csrss, and how to use CreateProcess in the Win32 API.