
Real-time operating systems 215
schemes where the operating system divides a task’s memory into
pages and swaps them between memory and mass storage. How-
ever, the operating system assumes complete control and such
schemes are totally transparent to the user.
With a single tasking operating system, it is not possible to
run multiple tasks simultaneously. Large applications have to be
run sequentially and cannot support concurrent operations. There
is no support for message passing or task control, which would
enable applications to be divided into separate entities. If a system
needs to take log data and store it on disk and, at the same time,
allow a ...