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.
Questions tagged [operating-systems]
229 questions
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How do I create my own programming language and a compiler for it
I am thorough with programming and have come across languages including BASIC, FORTRAN, COBOL, LISP, LOGO, Java, C++, C, MATLAB, Mathematica, Python, Ruby, Perl, JavaScript, Assembly and so on. I can't understand how people create programming…
Dave
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Why was Tanenbaum wrong in the Tanenbaum-Torvalds debates?
I was recently assigned reading from the Tanenbaum-Torvalds debates in my OS class. In the debates, Tanenbaum makes some predictions:
Microkernels are the future
x86 will die out and RISC architectures will dominate the market
(5 years from then)…
Robz
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How do operating systems… run… without having an OS to run in?
I'm really curious right now. I'm a Python programmer, and this question just boggled me: You write an OS. How do you run it? It has to be run somehow, and that way is within another OS?
How can an application run without being in an OS? How do you…
Thor Correia
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What operating systems are used in airplanes, and what programming languages are they developed in?
I was wondering if anyone knows what is the operating system used in commercial airplanes (say Boeing or Airbus).
Also, what is the (preferred) real-time programing language? I heard that Ada is used in Boeing, so my question is - why Ada? what are…
adhg
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What is meant by the phrase “Software can replace hardware”?
Studying beginners course on hardware/software interface and operating systems, often come up the topic of if it would be better to replace some hardware parts with software and vice-versa. I can't make the connection.
Gabriele Scarlatti
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Why is software OS specific?
I'm trying to determine the technical details of why software produced using programming languages for certain operating systems only work with them.
It is my understanding that binaries are specific to certain processors due to the processor…
user139929
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Is it a waste of time to free resources before I exit a process?
Let's consider a fictional program that builds a linked list in the heap, and at the end of the program there is a loop that frees all the nodes, and then exits. For this case let's say the linked list is just 500K of memory, and no special space…
Ramzi Kahil
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Why (not) segmentation?
I am studying operating systems and the x86 architecture, and while I was reading about segmentation and paging I naturally was curious how modern OSes handle memory management. From what I found Linux and most other operating systems essentially…
Mr. Shickadance
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Why not have a High Level Language based OS? Are Low Level Languages more efficient?
Without being presumptuous, I would like you to consider the possibility of this.
Most OS today are based on pretty low level languages (mainly C/C++)
Even the new ones such as Android uses JNI & underlying implementation is in C
In fact, (this is a…
rtindru
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Why don't Windows/Linux use relational Databases (RDBMS)?
Why don't Windows/Linux use relational databases (RDBMS)?
I know they use file systems to store all data but don't you think it is more efficient to use databases like we use in web sites/web apps?
Please elaborate on the use of a file system over a…
Pratik Joshi
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Why do modern operating systems *ever* have perceptible input (keyboard/mouse) lag?
Sometimes computers stutter a bit when they're working hard, to the point where the mouse location freezes for a fraction of a second, or stutters intermittently for a few seconds. This sometimes happens with keyboard input too, even in very basic…
Paul Calcraft
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Why aren't "fat binaries" more widely used for cross-platform applications?
As far as I know, so-called "fat binaries"--executable files that contain machine code for multiple systems--are only really used on Apple PCs, and even there it seems like they only used them because they needed to transition from PowerPC to…
Ixrec
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Why is it called a "trap" instruction?
To execute a system call, a program must execute a special trap
instruction.
Why is it called a "trap" instruction? What is the etymology of this usage of the word "trap"?
Is it related to the usual English word trap? Is something is getting…
littleO
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Kernel mode web servers: A clever optimization or a security nightmare?
I was reading a Hacker News thread where one user posts a link from 2011 explaining that IIS is much faster than most other (*nix) web servers. Another user replies, explaining that IIS gets that advantage by having a kernel module called HTTP.sys.…
James Mishra
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Is it possible to read memory from another program by allocating all the empty space on a system?
Theoretically, if I were to build a program that allocated all the unused memory on a system, and continued to request more and more memory as other applications released memory that they no longer need, would it be possible to read recently…
ConditionRacer
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