User mode

Programs that execute in the user protection domain are user processes.

Code that executes in this protection domain executes in user execution mode, and has the following access:

• Read/write access to user data in the process private region
• Read access to the user text and shared text regions
• Access to shared data regions using the shared memory functions

Programs executing in the user protection domain do not have access to the kernel or kernel data segments, except indirectly through the use of system calls. A program in this protection domain can only affect its own execution environment and executes in the process or unprivileged state.