Introducing the system call interface and system programming

Of course, the example that we just saw is simplified but gives us some idea about the work that the OS needs to do – in essence, it is responsible for managing and providing resources, but at the same time remains available for other processes’ requests. This is a messy job on modern OSs. Rarely can we do anything about it. So, to have better control and predictability of system behavior, programmers might directly use the OS’s API, called the system call interface.

Important note

The NVM data request is a procedure that benefits from the system call interface, as the OS will be obliged to turn this request into an application binary interface (ABI) call, referring to the respective device driver. Such an operation is known as a system call. Using system calls to implement or execute functions provided by the OS is known as system programming. The system calls are the only entry points to the kernel...