Kernel-Process Communication

The Kernel-Process Communication (KPC) describes how a process can interact with the kernel, and vice-versa.

There are two types of KPC:

• System calls, which are used by a process to ask the kernel to perform an action ;
• Signals, which are used by the kernel to send informations about an event to a process

Note that, unlike many operating systems like Linux, it's not possible for a process to send a signal to another. Only the kernel is allowed to emit signals.

For more advanced features, like permissions management or filesystem, check IPC.