Questions tagged [operating-systems]

The software layer between your hardware and application programs. It manages program scheduling, memory allocation, interrupt handling, disk input/output, graphic acceleration, hosting device drivers and various other resources.

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19answers
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32-bit vs. 64-bit systems

What are the differences between 32-bit and 64-bit systems? If you have used both of them, what kind of sharp differences have you experienced? Would it be a problem to use 32-bit programs on 64-...
108
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9answers
45k views

How much space to leave free on HDD or SSD?

In the informal (i.e. journalistic) technology press, and in online technology blogs and discussion forums, one commonly encounters anecdotal advice to leave some amount of space free on hard disk ...
92
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4answers
9k views

How does the computer know that the PC was not properly shut down?

Actually, this question struck me because of power cuts in my house. When there is a power cut, there is a sudden loss of power from the computer. How does the computer know that the shutdown was ...
76
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12answers
21k views

Does every OS need RAM?

Is there an OS which can be used without RAM, specifically the kind I can create a bootable pendrive from and use it in the computer? This gets awkward, since booting is essentially loading OS in RAM....
75
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5answers
49k views

What technical reasons exist for not using space characters in file names?

Somebody I know expressed irritation today regarding those of us who tend not to use spaces in our filenames, e.g. NamingThingsLikeThis.txt -- despite most modern operating systems supporting spaces ...
74
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7answers
33k views

Using UDF on a USB flash drive

After failing to copy a file bigger than 4G to my 8G USB flash drive, I formatted it as ext3. While this is working fine for me so far, it will cause problems if I want to use it to copy files to ...
71
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6answers
38k views

Does Windows still rely on MS-DOS?

I am just about to start an OS course and as an Apple user I am not very familiar with the underlying details of Windows OS. I was wondering, is MS DOS still used with Windows running on top or is ...
70
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8answers
20k views

Why is “Everything is a file” unique to the Unix operating systems?

I often hear people say "Unix's unique philosophy is that it treats everything as a file" or "In Unix, everything is a file". But I've never heard anyone explain why it is unique to Unix. So, why is ...
69
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8answers
22k views

How is virtual memory actually increasing the memory space?

I understand that virtual memory fools the program by displaying more memory than is actually available. But ultimately it has to map the logical address to the actually physical address. Now how is ...
62
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13answers
10k views

Is Unix not a PC operating system? [closed]

I am doing my bachelor's degree at a university. In a written assignment, the professor posted the task: "Name three PC operating systems". Well, I went on an included a variety of OSes (Linux, ...
58
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11answers
42k views

What is the relationship between Unix, Linux, Ubuntu, Debian and Android?

What is the relationship between Unix, Linux, Ubuntu, and Debian? I suspect they are all Operating Systems that are based upon one another - similar to how Windows is based on DOS. Is my suspicion ...
57
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2answers
79k views

Use physical harddisk in Virtual Box

Using Virtual Box, how can I install an OS to a secondary, physical disk, and boot it in both (at separate times) Virtual Box, and as a typical secondary OS install?
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11answers
9k views

Would an executable need an OS kernel to run?

I know that when the source code, in say C++, is compiled, the output from the compiler is the machine code (executable) which I thought were instructions to the CPU directly. Recently I was reading ...
52
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19answers
56k views

Is it still necessary to shut down computers?

Nowadays with our modern operating systems, is it necessary to fully shutdown computers instead of choosing to stand-by or hibernate computers (desktops and laptops)? Would there be any side-effects ...
50
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8answers
7k views

Before Operating systems, What concept was used to make them work? [closed]

The Operating systems have been tightly related to the computer architecture.An OS takes care for all input and output in a computer system. It manages users, processes, memory management, printing, ...
50
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3answers
97k views

How can I upgrade from Windows 7 to Windows 8 and keep my files and applications?

I want to upgrade from Windows 7 to Windows 8. How can I do this while keeping all of my files in-tact? Is it possible to retain all of my applications and user settings, too?
49
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11answers
4k views

Was Windows 95 an Operating System? [closed]

This question maybe a bit historical, but we didn't have Superuser at the time. Around 2000 when I was starting my Computer science degree, a subject was Operating systems. The teacher asked us to ...
46
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4answers
8k views

How computers display raw, low-level text and graphics

My ever-growing interest in computers is making me ask deeper questions, that we don't seem to have to ask anymore. Our computers, at boot, as far as I understand it, are in text mode, in which a ...
43
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2answers
6k views

What is there in an Operating System other than the kernel

As I understand it, the kernel does all the interaction with the hardware, and manages the memory, the I/O devices, etc. So the kernel is doing everything, yet it is just a part of the operating ...
43
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7answers
11k views

How to make VIM settings computer-dependent in .vimrc?

I share my VIM configuration file between several computers. However, I want some settings to be specific for certain computers. For example, font sizes on the high-res laptop should be different to ...
42
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1answer
75k views

cat /proc/meminfo what do all those numbers mean

In reading the man page on the free command in Linux. I found that is gets its info from /proc/meminfo. I understand a few of the entries, like MemTotal and MemFree. What do the rest mean. cat /...
41
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10answers
4k views

What does an operating system look like without a shell?

A shell like the bash or command.com (up to Windows ME) or CMD.EXE (in later versions) provides an interface that (among other things) accepts commands from the user. What does an operating system ...
41
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1answer
4k views

Do 64bit software/applications require more RAM than their 32bit counterparts?

I just saw these minimum requirements for a game: Memory: 2GB for 32-bit OS or 4GB for 64-bit OS Why does the 64bit OS require more RAM than its 32bit counterpart?
40
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7answers
11k views

Other benefits of 64-bit OS apart from memory expansion?

I'm trying to convince somebody of the benefits of switching to a 64-bit OS but I'm having a hard time finding arguments other than "you can use more than 3GB RAM". Are there any other clearly-...
39
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4answers
5k views

Linux is to mount as Windows is to _______?

So Linux "mounts" a hard drive to perform some operation such as reading/writing. Does Windows "mount" in the same way? Is it called something different in the context of Microsoft?
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3answers
10k views

In Linux what happens if 1000 files in a directory are moved to another location while another 300 files were added to the source directory?

In Linux what happens if 1000 files in a directory are moved to another location and another 300 files were added to the source directory while original 1000 files were being moved. Will the ...
36
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5answers
163k views

What would happen if I take my hard drive out of my current PC and put it in a new PC?

Basically, I want to get a new PC, but I have so many software/games installed on my current hard drive, that I don't want to waste the time to re-install/re-configure. Would it work if I just take ...
35
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1answer
3k views

65536 +1 Connection on a system

There are 65536 ports for every system in the network, and every connection or Send/Receive will use one of those. My question is: what happens if we have 65536+1 connections?! I know that it ...
34
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3answers
8k views

How is the operating system able to know the battery level?

Even if we remove the default OS and install a new one it can interact with the battery. Are there some drivers for it? How does it work?
27
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13answers
14k views

Non-Windows, non-Unix-like OS's?

Since most operating systems I've heard of besides Windows seem to derive their heritage from Unix, I've been curious whether any OS's with the following characteristics exist: Not generally ...
26
votes
2answers
15k views

How can the BIOS block virtualization?

I'm starting to work with Docker and after a few hours of trying to make it work, I found out that my BIOS was blocking it and that I needed to adjust the BIOS settings. I was told that the BIOS is ...
26
votes
8answers
55k views

Are we supposed to manually delete the contents of /tmp?

I was under the impression that “old” files in /tmp will be regularly deleted. However, it seems to me that /tmp will just grow as long as it wants to, and nothing will be deleted. Some people say it’...
23
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4answers
6k views

Why does Linux use a swap partition when the kernel supports paging/virtual memory anyway?

As far as I understand paging and swapping, they're completely different concepts. While swapping means, that a process is either completely in physical memory or on the hard drive, with paging parts ...
23
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4answers
140k views

Can a 32 bit OS run in a 64 bit processor?

What's the difference between 32 bit OS and 64 bit OS? Can a 32 bit OS run in a 64 bit processor?
23
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3answers
2k views

Why can't I change the name of a file that's being read on Windows as I can do on Linux/Mac?

One of the things that has puzzled me ever since I started using Linux is the fact that it allows you to change the name of a file or even delete it while it is being read. An example is how I ...
22
votes
9answers
153k views

How can I determine the OS of a remote computer?

How can I determine the OS of a remote computer, given its computer name?
22
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4answers
3k views

Can unexpected power loss harm a Linux install?

I am developing an application on a Linux embedded board (runs Debian) e.g. Raspberry Pi, Beagle Board/Bone, or olimex. The boards works on an environment that the electricity is cut unexpectedly (it ...
22
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3answers
8k views

What are the technical differences between Windows Vista and Windows 7?

I'm interested in finding an unabridged technical manual documenting all of the differences between the two operating systems. In Tanenbaum's latest edition of Modern Operating Systems (3rd Edition), ...
21
votes
2answers
415 views

What is it that makes Windows require constant rebooting while Linux does not? [duplicate]

Like many people, I run dual systems on my computer. Important updates require constant reboots on Windows, while I don't think this ever happened to me on Linux. What properties of each OS decides ...
21
votes
5answers
728 views

Why does VM software need to know which OS will be running inside the VM?

When I create a new VM (with VirtualBox) it will ask me what OS will run inside the VM. Why does it need (or like) to know that? Will it result in better performance? Will some things work / not work?...
20
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2answers
3k views

Why are operating systems (usually?) unable to access BIOS settings?

Does the motherboard not provide a bus between the CPU and BIOS chip after bootup? If so, why not? If the CPU can control fan speed, I don't see why it shouldn't be able to control the BIOS config.
20
votes
1answer
29k views

How do preferred and alternate or multiple DNS servers work?

I was considering adding 8.8.8.8 to the end of my adapter's list of DNS servers as a backup in case everything fails, when it occurred to me that I don't really know how secondary and tertiary DNS ...
20
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2answers
33k views

A Dark Theme for Windows 8

Is there any way for me to use Windows 8 in a dark environment? For a long time I had headaches that I couldn't fid their cause. Now, I'm using a dark visual style for my Windows 7 and since then, I ...
18
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2answers
4k views

Computer architecture: Are USB keyboards less responsive due to narrow IRQ range?

Here is a statement I just thought of. Can anyone tell me whether, and why, it is true? Statement: Because USB keyboards rely on a USB generic driver and architecture that has only access to lower ...
17
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5answers
4k views

Does dual-booting an OS require a dual-core processor?

My friend claims that dual booting, using two different OSes, requires a multi-core or multi-threaded processor. Is this true? And if I install additional OSes, will my computer slow down any?
17
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4answers
118k views

Should I install my operating system on my SSD or HDD?

I'm currently deciding whether to install my Operating System on my SSD (solid state drive) or HDD (hard disk drive). Should I install programs on the HDD and the OS on the SSD or vice versa? Which ...
16
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9answers
7k views

To what extent can a computer be reset to factory settings?

Our teacher gave us 2 used computers and asked us to format them and we did. Then we installed Windows 10 on both. Now he comes and says "I don't want any OS on them". Of course, when a computer is ...
16
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3answers
17k views

Why can't computers boot instantly?

Computers have been around for quite some time. So what is stopping us from making computers boot instantly like regular home appliances and other devices? Is it even possible? I know there is ...
16
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6answers
25k views

Does low disk space affect SSD performance?

I was wondering if having less than 5-10GB of free space on an SSD would affect performance. Is it specific to SSD or is it more of an operating system aspect? For example, on an Intel X-25 G2 that ...
15
votes
5answers
78k views

Memory limits in 16, 32 and 64 bit systems

The theoretical memory limits in 16, 32 and 64 bit machines are as follows: 16 bit = 65, 536 bytes (64 Kilobytes) 32 bit = 4, 294, 967, 295 bytes (4 Gigabytes) 64 bit = 18, 446, 744, 073, 709, 551, ...