Questions tagged [operating-systems]

An operating system (OS) is a basic software whose rule is to intermediate software requisitions for resources and the hardware available, manage input/output, memory allocation/deallocation, file systems, among other basic tasks a device should do.

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Are there any OS which are simple enough for learning?

I would really like to understand how an operating system works behind the scenes. However, I think that the kernel of most open-source OSs out there are too complex for learning purposes, even for a full-time programmer to learn. Are there any…
DotNetStudent
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How does multitasking work

I am completely clueless about the inner workings of an operating system, but I can more or less guess the approximate behaviour of many functions. One thing that I am not able to figure out, though, is multitasking. In theory, the operating system…
Andrea
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OS Development in C++ Questions

As a Master's project, I am designing a simple operating system. It is being designed to run in 16-bit Real Mode on an x86 architecture. Ideally, I would like to develop this OS in C++, and only using assembly where necessary. Thus far, I have a…
bunglestink
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How to operate a computer without an operating system?

How a computer can be used when there is no operating system? What tools or knowledge do I need to do it? Do I have to give all the commands in binary to use computer hardware resources like a monitor?
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How does a program make a system call

I'm reading Tanenbaum's Modern Operating Systems and I really can't grasp the following concept: how does a program make a system call? I mean, i got the very basics down (correct me if I'm wrong): the OS is just another program running on the…
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Trying to understand OS-Level Virtualization

I'm trying to learn more about the fundamentals of containerization. I came across the term "OS-Level Virtualization" as the partitioning of the user space to further increase process isolation. However, I have two questions about this what is the…
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Regarding system interrupts and timers. Why programs sometimes still run when OS asks you to terminate or keep it going?

I'm reading (just started) "Operating systems concepts" by Silberschatz, Galvin and Gagner and something called my attention when reading a basic primer on "timer" (1.5.2 on the book). It says: As long as the counter is positive, control is…
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Is learning about operating systems useful for a software developer?

Most of the underlying workings of the operating system is hidden from the programmer. I believe that is also one of the purposes of an operating system. Then what are the reasons a software developer should learn about how operating systems work?
Kake_Fisk
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What is a Real-time system

What is the most appropriate definition of a Real time system? Is online railway reservation a real time system ? Is Aircraft control system a real time system? Is Process control system a real time system?
Zubair
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Still confused why a monolithic operating system is faster than a layered operating system

In the book Operating System Concepts, In the summary it states: A monolithic operating system has no structure; all functionality is provided in a single, static binary file that runs in a single address space. Although such systems are difficult…
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Why high-tech OSs (like UNIX family) are mostly command based (rather than GUI based)?

DR-DOS, Plan, BSD, Sun Solaris, HP/UX, OpenServer.....and so on. Why high-tech OSs (like UNIX family) are mostly command based (rather than GUI based)?
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What's contained in 'kernel mode' in virtual address space of a process?

I'm reading through Mickens' OS notes, and I came across the following depiction of a virtual address space. I conceptually understand "user mode" of a process' virtual address space. It contains program instructions, stack, heap, static data,…
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System Call Interface and operating system API

What is the difference between operating system API and system-call interface ? I have read at many places that both act as interface between program and the kernel. Then what is the actual difference between them ?
Vedant Pareek
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Asynchronous communication from synchronous communication

Studying Inter Processes Communication in Operating System, I've discovered that asynchronous communication can be built on top of synchronous communication. But, it's not clear to me how can it be done. Can you explain to me ? :)
Qwerto
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How does the operating system regain control when multitasking?

I get how multiple processes can run on a single core by interleaving the processing. What I don't understand is how the operating system ensures that the program releases the processor after a certain amount of time. If only one program can run at…
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