Kernel functions

• Forms the core of the OS, and must contain minimal functionality.
• Should be implementable in a high level language such as C.

The Kernel performs

• Management of processes
  Process Data structures and context
  the creation, deletion, starting and stopping of processes.
• First level interrupt handling
  Support for both interrupt and device handlers.
• Multiplex (share) processor between processes
  Act as a Dispatcher and as a Low level scheduler
• Provide a mechanism of interaction between processes
  Achieved via a number of different primitives
  semaphores, locks and/or message passing.
• Timer functions
  delay for a period, time and date and accounting (measuring run time performance).
• Interrupt handling

Note: In some systems, I/O is part of kernel (Unix).