Byobu vs. GNU Screen vs. Tmux

So far I have used Konsole to manage multiple shell sessions but I haven't tried Byobu, GNU Screen, and tmux, which offer better support for multiple shells. They all share one main feature, which... | Continue reading


@superuser.com | 2 years ago

Why does Windows have a limit on environment variables at all?

What the Technical Reasons for 1024 character limitAfter having used Linux for the past 3 years, so many Windows 7 Pro issues have been bothering me at my day job. The most inane are the filename... | Continue reading


@superuser.com | 2 years ago

Super User is currently offline for maintenance

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@superuser.com | 2 years ago

Transatlantic ping faster than sending a pixel to the screen? (2012)

John Carmack tweeted, I can send an IP packet to Europe faster than I can send a pixel to the screen. How f’d up is that?And if this weren’t John Carmack, I’d file it under “the interwebs being | Continue reading


@superuser.com | 2 years ago

Ran a PowerShell script, Was I hacked?

I was an idiot and was suckered into running a PowerShell script.Can anyone tell me details about it?I have a feeling they only uploaded some files from my system.But I am worried there may be a | Continue reading


@superuser.com | 2 years ago

Removing dead thunderflies stuck inside an LCD monitor (2009)

This summer my flat was "attacked" by hundreds of tiny thunderflies, some of which managed to get behind the screen of my LCD. A few of the cursed creatures went and died right in the middle of the | Continue reading


@superuser.com | 2 years ago

Firefox 91 – Revert back to old tab style

The recent update (89 I think) causes all tabs to render in the same continuous shading, which makes it somehow more difficult to spot each tab's start and end (regardless of the favicon, I'm sorry, | Continue reading


@superuser.com | 2 years ago

How to disable Google One Tap sign-up prompts?

I've recently begun seeing common pop-ups on sites on which I do not have an account.The pop-ups prompt me with my real name and Google sign-in email, which is being provided either by being signe... | Continue reading


@superuser.com | 2 years ago

How and why is this string of text a fork bomb?

Found on a random chan board:echo "I<RA('1E<W3t`rYWdl&r()(Y29j&r{,3Rl7Ig}&r{,T31wo});r`26<F]F;==" | uudecodeSomehow running this this results in an infinitely spawning proc... | Continue reading


@superuser.com | 2 years ago

Micro-USB 2 cable in a USB 3 portable hard drive

The micro-B USB 3 port seems to be somewhat backwards compatible with the old micro-USB 2 standard. I was able to charge a phone that had the micro-B USB 3 port with a micro-USB 2 cable.However, ... | Continue reading


@superuser.com | 2 years ago

Firefox writes megabytes of data per minute to disk, why?

iotop -a (accumulated I/O) on Linux shows after about 10 min. of browsing Internet:Total DISK READ: 0.00 B/s | Total DISK WRITE: 0.00 B/s TID PRIO USER DISK REA... | Continue reading


@superuser.com | 2 years ago

What is the shelf life of unused/unburned CD-R/CD-RW disks? (2014)

I have a lot of old unused/unburned CD-R/CD-RW media. Are there published test results documenting the expected shelf life of this type of media? | Continue reading


@superuser.com | 3 years ago

Storing DVDs in a Cooler (2017)

I am trying to create the most optimal storage environment for some DVDs in my living space. I often open my window to maximize airflow, this tends to create significant temperature fluctuations.... | Continue reading


@superuser.com | 3 years ago

What is randomart produced by SSH-keygen? (2009)

When you generate a key, you get "randomart" from newer versions of OpenSSH. I am unable to find an explanation of why, and what I'm supposed to use it for.Generating public/private rsa key pair.... | Continue reading


@superuser.com | 3 years ago

How does a computer restart itself?

How can a computer restart itself? After it's off, how does it tell itself to come back on again? What kind of software is it that can do this? | Continue reading


@superuser.com | 3 years ago

Any wireless short range alternatives to 2.4ghz and 5ghz WiFi? (2020)

Moved to a new apartment, the building is flooded with wifi networks. Both 5ghz and 2.4ghz bands have 30+ SSIDs floating around, the packet loss is pretty bad. Its not really noticeable while just | Continue reading


@superuser.com | 3 years ago

Why are tar.xz files 15x smaller when using Python's tar compared to macOS tar?

ContextI'm compressing ~1.3 GB folders each filled with 1440 JSON files and find that there's a 15-fold difference between using the tar command on macOS or Raspbian 10 (Buster) and using Python's... | Continue reading


@superuser.com | 3 years ago

Why are tar.xz files 15x smaller when using Python's tar compared to macOS tar?

ContextI'm compressing ~1.3 GB folders each filled with 1440 JSON files and find that there's a 15-fold difference between using the tar command on macOS or raspbian buster and using Python's buil... | Continue reading


@superuser.com | 3 years ago

You can have a maximum of 127 ports on a USB controller

Would attaching a 4 port USB-3 hub to a port on a USB-C to USB-3 hub cause problems? | Continue reading


@superuser.com | 3 years ago

Pasted all the “text” from JPG with Notepad to a new file but it no longer opens

This phenomenon has been leaving me questions to ask.Here is the detailed experiment, my OS is Windows 7 x64 SP1:I changed a picture (JPG) file to TXT by simply changing its extension (or one c... | Continue reading


@superuser.com | 3 years ago

Keyboards variants with different enter keys (ANSI, ISO, JIS, ABNT)

I'm a programmer, and a touch-typist, and so type best when the keys I use are where I expect them to be. Perhaps because I'm American, and do most of my work on Apple computers, I expect the keybo... | Continue reading


@superuser.com | 3 years ago

Use Bluetooth keyboard to access/edit BIOS? – Super User

Can I use a bluetooth keyboard to enter BIOS and edit the values there? I'm thinking of two scenarios:A new machine - no OS (yet). So to me seems no possibility to pair the keyboard. Hence no acc... | Continue reading


@superuser.com | 3 years ago

What is the expected behavior when holding down two keys on a keyboard?

ContextA friend and I are playing a game where the optimization to playing a given character in the game is to hold down two buttons at once, i.e. they keys Q and E. This would mean that within th... | Continue reading


@superuser.com | 3 years ago

Why does Windows think that my wireless keyboard is a toaster? (2014)

I've inherited an old PC from my girlfriend's dad and when setting up the printer I got a bit of a surprise:Two questions spring to mind here:Why does Windows think my wireless keyboard is a to... | Continue reading


@superuser.com | 3 years ago

In /proc/meminfo, what is the difference between 'MemFree' and 'MemAvailable'

You might see something like this if you cat /proc/meminfo:MemTotal: 8078760 kBMemFree: 629012 kBMemAvailable: 1175568 kBBuffers: 126184 kBCached: 2988512... | Continue reading


@superuser.com | 3 years ago

Disable pop-ups for “Sign in to WEBSITE with Google”

Recently I've begun to see common pop-ups when visiting sites on which I do not have an account.The pop-ups prompt me with my real name and Google sign-in email, which is being provided either by ... | Continue reading


@superuser.com | 3 years ago

What Firewall Rule(s) Will Allow Windows Update and Only Windows Update to Work

What Firewall Rules Will Allow Windows Update and ONLY Windows Update to Work For Windows 8.1? If that is not possible please provide the minimum rules necessary and the names of the additional pr... | Continue reading


@superuser.com | 3 years ago

Why can't I find a USB-C hub with multiple USB-C ports?

My computer only has one USB-C port and I want to connect multiple USB-C devices to it.I have trawled through Amazon but am amazed that I cannot find a single one. There are many hubs that have U... | Continue reading


@superuser.com | 3 years ago

How does a computer restart itself? [StackExchange]

How can a computer restart itself? After it's off, how does it tell itself to come back on again? What kind of software is it that can do this? | Continue reading


@superuser.com | 3 years ago

Reading a PDF file on Google Chrome on 2 columns

Is there any way to display a PDF file on two columns on Google Chrome?I.e. instead of having:I would like to see something like:3 columns would be even nicer in some cases. | Continue reading


@superuser.com | 3 years ago

What does the 'rc' in `.bashrc`, etc. mean?

Well, this is embarrassing. I feel like I just realised I don't know a loyal colleague's name after working with them for 10 years. "Hey, er... *cough!*, thanks for that great job you did on settin... | Continue reading


@superuser.com | 4 years ago

Speedtest-CLI the official one is unreliable because too old and Python

I'm encountering a strange problem here.On my local homeserver(Debian 9.9), speedtest-cli and it's python pendant are freaking slow.Since I use it to monitor my ISP connection stability, this is a | Continue reading


@superuser.com | 4 years ago

Why does gigabit internet via coax cable not offer symmetrical speed like fiber?

In our area, we have Cox Communications (cable) which offers 1 Gbps down, and 30 Mbps up, while Century Link (fiber) offers 1 Gpbs up AND down. Why does copper only 'allow' fast speeds for downlo... | Continue reading


@superuser.com | 4 years ago

Why Coax Internet Cannot Offer Symmetrical Speeds

In our area, we have Cox Communications (cable) which offers 1 Gbps down, and 30 Mbps up, while Century Link (fiber) offers 1 Gpbs up AND down. Why does copper only 'allow' fast speeds for downlo... | Continue reading


@superuser.com | 4 years ago

Google Chrome cannot display URL schemes without installing an extension

A couple of days ago I noticed that for all websites, chrome omits from the address bar the protocol and the subdomain if it is www. My co-workers report that they are not seeing this. Chrome versi... | Continue reading


@superuser.com | 4 years ago

How do I activate Windows XP in 2019?

What Options are there to activate Windows XP nowadays, the regular methods provided with XP (phone and online) don't work anymore. The phone number is not valid for activation anymore and the online | Continue reading


@superuser.com | 4 years ago

Being able to see the tracks and bits in a CD-ROM

I have 3 copies of a CD-ROM that came with a book, and all of them came cracked.By the third time, I thought that I could probably recover the information using these 3 different discs and comple... | Continue reading


@superuser.com | 4 years ago

Opera imports everything from Chrome, including OAuth2 tokens

I've recently installed Opera browser in unattended mode (using Chocolatey: choco install opera). When I opened it for the first time, Opera had all my bookmarks imported from Chrome (unwanted, but... | Continue reading


@superuser.com | 4 years ago

What's the quickest way to count the number of each character in a file?

I want to count the A's T's C's G's N's and "-" characters in a file, or every letter if needed, is there a quick Unix command to do this? | Continue reading


@superuser.com | 4 years ago

“Example.com” vs. “Example.com.”

Consider:When I put a dot after the Super User URL, https://superuser.com., it acted like I wasn't signed in. Why is this happening? What does a dot symbolize in the URL? | Continue reading


@superuser.com | 4 years ago

Why does putting a dot after the URL remove login information?

When I put a dot after the superuser URL, it acted like I wasn't signed in. Why is this happening? What does a dot symbolize in the URL? | Continue reading


@superuser.com | 4 years ago

What if I revoked my GPG subkey that was used for SSH authentication?

IMHO, the key is still valid for ssh authentication on a remote server.If so, what's the best practice to revoke a gpg key for ssh authentication? | Continue reading


@superuser.com | 4 years ago

Motherboard won't power down completely until display port is unplugged

A couple of days ago I bought two new monitors (iiyama g-master GB2730HSU-B1), and by doing so I also switched to using display port instead of HDMI (EVGA GTX 970 graphics card).Now a weird issue... | Continue reading


@superuser.com | 4 years ago

Why can't computers boot instantly? (2013)

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 hibe... | Continue reading


@superuser.com | 4 years ago

How Do Ctrl+C and Ctrl+V Work?

I was always wondering what happens under the hood (in the operating system) when I copy an image (selecting it and using Ctrl+C) into a Word file (pasting it with Ctrl+V), for example. | Continue reading


@superuser.com | 4 years ago

How to temporarily freeze a process in Linux

I was wondering if there is a way to freeze any process for a certain amount of time?What I mean is that: is it possible for one application (probably running as root) to pause the execution of a... | Continue reading


@superuser.com | 5 years ago

How to Clear/Flush the DNS Cache in Google Chrome?

As you probably know Google Chrome has its own internal DNS cache. Is there a way to clear it without having to wait for the time out or close the browser? | Continue reading


@superuser.com | 5 years ago

Chrome ignores silenty “Clear cookies on exit” keeping them forever

I'd like to remove cookies when I close Chrome, but only for a certain site. Chrome can do this, or says it can, but it doesn't work. When I restart Chrome the cookie for the site is still there. I | Continue reading


@superuser.com | 5 years ago