1) Background:
In the early days, if you want the computer to execute the program, you need to refer to a lot of hardware function functions when writing the program, and you need to learn machine language to write it,
so if you change another machine, the program cannot run. , the program needs to be changed
, so it is quite troublesome, so people imagine that there
can be something as an intermediary that can drive all the hardware and provide a development interface for engineers to develop programs
. In this way, the operation of the program is only You need to see if it is the same operating system, without worrying about hardware functions (because in life, there are only a few sets of operating systems, but the hardware is different, huge!!)
The operating system was born~
2) Operating system kernel:
The operating system kernel is actually
a group of programs .
The focus of this group of programs is to drive the hardware and manage all the activities of the computer. All operations of the
hardware
must be completed by the operating system. This is the function of the kernel, and only the kernel provides these functions. Your computer system can do it for you. Because the kernel is so important, the blocks placed by the kernel program are protected and remain resident in memory after booting.
3) System call:
Literally we can see that this is
named for calling the operating system
, and we mentioned earlier that the operating system kernel is the middleman between the program and the hardware, so it is not difficult to imagine that
this system call is actually provided by the operating system to the A set of interfaces for an engineer to develop a program. The
program is developed according to this set of interfaces, which is equivalent to a program developed by an engineer with reference to the kernel function
. With the function that can call the operating system, the operating system will automatically use the hardware resources according to the program. To call the hardware
, so we can find that the software has a relatively large relationship with the kernel, and has little to do with the hardware, and the hardware has a relatively large relationship with the kernel.
4) Kernel functions:
system call interface, program management, memory management, file system management, device driver
——讲完操作系统和应用程序的关系，我们再看下操作系统和硬件的关系——
我们都知道，硬件都是时刻在进步着的，但是硬件和操作系统的进步并不同步，那么是不是意味着我们的操作系统只能用和它匹配的硬件而不支持最新的硬件？所以，为了解决这个问题，操作系统又提供了一组开发接口给制造操作系统的厂商，让他们参照内核的功能来开发驱动程序，如此一来只要用户安装了最新的硬件的驱动程序，那么就可以轻轻松松用上跑起最新的硬件来了