The main difference between kernel and shell is that the kernel is the core of the operating system that controls all the tasks of the system while the shell is the interface that allows the users to communicate with the kernel.
When his sons Marcus junior and Samuel were looking for a name for the kerosene that they were exporting to Asia, they chose Shell. Shell functions are a way to group commands for later execution using a single name for the group.
When the name of a shell function is used as a simple command name, the list of commands associated with that function name is executed. A core feature of any operating system, the kernel manages communication between hardware and software. It also handles device signals, task scheduling, and other essential duties.
If you imagine it geometrically, the origin is the center, sort of, of a Euclidean space. It can be conceived of as the kernel of the space. The kernel itself is not a process but a process manager. The operating system kernel represents the highest level of privilege in a modern general purpose computer. The kernel arbitrates access to protected hardware and controls how limited resources such as running time on the CPU and physical memory pages are used by processes on the system.
A kernel is the central part of an operating system. It manages the operations of the computer and the hardware, most notably memory and CPU time. There are five types of kernels: A micro kernel, which only contains basic functionality; A monolithic kernel, which contains many device drivers. The Kernel is part of the operating system — And the most crucial. And yes, the calls you mentioned are regarded as API calls. The request to these calls are also handled by Kernel.
Please go the below link to find API calls in unix. Consider an example, You are watching the movie is on shell and actually process done over hardware is the kernel. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams?
Collectives on Stack Overflow. Learn more. Asked 9 years, 2 months ago. Active 1 year, 5 months ago. Viewed 51k times. Can the functions like printf and fopen in C be called API calls?
Add a comment. Active Oldest Votes. The first volume of the Unix manual pages contains the shell commands. Than I wish to know one more thing. Is there any such thing as Windows Shell?
What about situations where we have a GUI instead of a command line prompt? This is the only last thing I do not yet understand. Anyway, the fact there is a GUI doesn't make a difference. Whether you use windows, Gnome or KDE, you can run a shell or equivalent in a command line window terminal emulator. Bossliaw fopen and printf have a lot of specific code and share tables, buffers and context with each other.
For that reason, I don't call them wrappers to system calls, especially as for example you can call printf without any system call being involved. They just sometimes happen to eventually use system calls but this is true for every library function.
The link you posted as reference which I totally agree with doesn't say anything that contradict that point. My point is that a shell, or a collection of shells are not the only outermost layer of an operation system. There are so much bogus diagrams wrongly presenting the shell s as a real layer while they are just programs like the others.
See for example unix. Show 3 more comments. Ahah, so Shell is merely a command line. So the cmd in windows is the Shell for windows or DOS?
Neither, because windows and other OS do not need to have a shell. Maybe shell should be renamed as default interface to the OS services? So our windows GUI environment with all the icons is not Shell or is it?
Is the Dos prompt Dos shell? Uwe Plonus 9, 4 4 gold badges 37 37 silver badges 47 47 bronze badges. Sanket Sanket 11 1 1 bronze badge. And what is API in this example? Sign up or log in Sign up using Google. Sign up using Facebook.
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