IOS Kernel

When used within the context of operating systems, the word kernel usually conjures pictures of an operating system core that runs in a special protected CPU mode and manages system resources. Although the IOS kernel does help manage system resources, its architecture differs from those in other operating systems. The IOS kernel is not a single unit but rather a loose collection of components and functions linked with the rest of IOS as a peer rather than a supervisor. There's no special kernel mode. Everything, including the kernel, runs in user mode on the CPU and has full access to system resources.

The kernel schedules processes, manages memory, provides service routines to trap and handle hardware interrupts, maintains timers, ...

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