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Questions tagged [unix]

Unix is a multitasking, multi-user computer operating system originally developed in 1969 by a group of AT&T employees at Bell Labs.

Excerpt from the Wikipedia page

Unix was originally written in assembly but has since been rewritten in C. It has been branched many times both commercially and open source. One popular variant is the BSD variant which originated from the University of California, Berkeley. It also gave rise to Linux.

Notable variants

  • Silicon Graphics - Irix
  • IBM - AIX
  • Sun Microsystems - Solaris
  • Hewlett Packard - HP-UX

Unix is officially trademarked as UNIX.

Unix on Wikipedia

1949 questions
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Does iowait include time waiting for network calls?

The proc(5) manpage describes iowait as "time waiting for IO to complete". This was mostly explained in an earlier question. My question is: while waiting in blocking IO, does this include waiting on blocking network IO, or only local IO?
Alex J
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Putting a process in the background without stopping it - (ctrl+z)?

If I start a process by typing it in normally at the command line, such as wget http://site.com/bigfile.zip and then decide I want to move that to the background, I know that I can use something like ctrl+z and then bg 1 (or jobs first if needed…
cwd
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Make ls print it all on one line (like in terminal)

ls prints differently depending on whether the output is to a terminal or to something else. e.g.: $ ls . file1 file2 $ ls . | head file1 file2 Is there some way to make ls print out on one line as if it's to a terminal when it's not. There's a -C…
Amandasaurus
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How big (in bits) is a Unix UID?

I understand that unix user IDs (UIDs) are usually 16 or 32 bit unsigned integers but how can I find out for any given system (in a shell)?
Josef
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2 answers

What is the sticky bit in UNIX file systems? When is it used?

What is the sticky bit in a UNIX file system? As an admin when and how would you use it?
Aaron K
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3 answers

Override MAILTO for a single crontab entry

We have a role account at work that has a pretty big crontab. Its MAILTO is pointed at a shared address, so that a number of us get notified if something fails. I'd like to add an entry to this crontab, but I only want myself to be notified if…
mike
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8 answers

Linux - use "su -" but keep the current directory

When I do su - to get to root, my current directory is set to root's home. Is there anyway to keep the current directory that I was in, much like sudo -s. Or is the answer to use sudo?
Amandasaurus
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3 answers

Approximately how much would it cost to make an AMI image from a EC2 Micro server?

If I do this 10 times a month, how much would that cost me?
Alex
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4 answers

What's the best way to clean up after a fork bomb?

$ ls bash: no more processes Uh oh. Looks like someone made a fork bomb. Where I used to work, this pretty much meant that the shared server would need to be power-cycled, since even the sysadmins with root often couldn't get the problem cleaned…
raldi
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9 answers

Monitor network traffic volume over interface

Is there a way to monitor the traffic (e.g., get a live view of the utilization) over a particular network interface, say eth0? The catch here is that the set of tools on the box is fixed, and is pretty much a stock RHEL deployment, so add-on tools…
BeeOnRope
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When would ssh -t not be appropriate instead of ssh?

Using ssh -t instead of ssh for connections to remote servers has several advantages. For example, I can directly edit a file with vim: ssh -t host vim foo.txt, which would fail otherwise. Are there any circumstances under which allocating a…
Alex J
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dmesg time vs system time time isn't correct

I hope that here is somebody that can help me with this strange problem. I think that i know why it is happening but i don't know how to solve it. Maybe it is because the BIOS time isn't set correct or something like it. But i don't want to change…
g00gle
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1 answer

Does directory mtime always change when a new file is created inside?

Is it always true that when a new file is created in a directory - the directory's mtime changes?
kolypto
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9 answers

Is it possible to hide lost+found?

Given a partition intended solely for storing music, video and so-on, is it possible to hide the lost+found directory?
jldugger
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Is there a utility to read environment variables from an env file and then run a command (more lightweight than foreman)?

foreman can read .env files and set environment variables from the contents, and then run a program e.g. foreman run -e vars.env myprogram ...but it does a lot of other things (and is primarily concerned with starting things using its Procfile…
wodow
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