A shell is software that lets users interact with the operating system, usually by typing at a command-line.

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Determine Linux distribution

I am trying to determine what flavor of linux server is running. I am not trying to determine the kernel version - but rater the distributor. gcc is installed, and in the version output, it says ...
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How long is long for the Unix 'file' command?

When you pass a text file to the Unix file command, it might tell you something like: input.txt: UTF-8 Unicode English text, with very long lines Can somebody tell me the minimum number of ...
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4answers
777 views

Is it possible to print out the shell expansion?

I know there is a specific set of rules that shell expand the commands user typed. (let's talk about bash shell.) Is it possible to print out a command in the form after shell expansion? It seems to ...
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4answers
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echo newline character not working in bash

I have bash script which has lots of echo statements and also I aliased echo to echo -e both in .bash_profile and .bashrc, so that new lines are printed properly for a statement like echo 'Hello\...
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3answers
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Mouse cursor in Terminal?

I use Mac OS X Terminal.app. But the answer to this would probably apply to any typical UNIX-ish terminal emulator in a graphical environment. Question -- what do I do to: Use my mouse cursor to ...
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2answers
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How can I found out if file is alias or symbolic link?

I'm working on a legacy system and I have a bunch of files that are referencing images that are located in other folders. lrwxrwxrwx 1 user nobody 56 Feb 10 2010 t100x100.jpg -> /home/www/...
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4answers
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Better way to do “echo $x | sed …” and “echo $x | grep …”

I often find this in scripts (and, I have to admit, write it myself): a=$(echo "$x" | sed "s/foo/bar/") or if echo "$x" | grep -q foo then ... fi Consider "foo" to include some regex stuff. ...
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12answers
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Best way to organise one's sh/bash/python/etc. scripts

What is the best way to organise the sh/bash/python scripts you collect and write on your system?
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5answers
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Linux command to return number of bits (32 or 64)?

What is a Linux command that I can run to programmatically return either 32 or 64 to indicate whether the processor is a 32 bit or 64 bit processor?
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1answer
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How do I unset or get rid of a bash function?

If you set or export an environment variable in bash, you can unset it. If you set an alias in bash, you can unalias it. But there doesn't seem to be an unfunction. Consider this (trivial) bash ...
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5answers
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gzip all files without deleting them

I need to gzip all files in a dir separately including all files in sub-directories without deleting the originals afterwards. So let's say I have index.html, I want to have at the end index.html.gzip ...
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4answers
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Get the parent directory for a file

I want to get just the name of the parent directory for a file. Example: When I have path=/a/b/c/d/file, I want only d and not /a/b/c/d (which I get from dirname $path) as output. Is there any ...
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2answers
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Indicating end of Standard Input

How does one indicate that one has finished entering test in stdin? For example, let's say that I wish to encrypt 'blue' using MD5 (I know MD5 is unsecure, but just for this example). I tried user$ ...
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5answers
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Is there a way to escape single-quotes in the shell?

E. g. I want to say perl -e 'print '"'"'Hello, world!'"'"', "\n";' Is there a less awkward way to do it, e. g. escaping single-quotes? Yes, I know that I can write perl -e 'print q[Hello, world!],...
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1answer
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Vim Ignores Aliases

If I map a command in vim using something like map <f4> :! pdflatex %<cr> Vim will ignore my alias for pdflatex (something like alias pdflatex='pdflatex --temp-dir=something'). Is it ...
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3answers
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Why does less tail mode stop working?

Using the less command on linux in tail mode (F command or less -f) consistently stops working on certain machines and/or certain files. New changes simply stop showing up. I know I've fixed this ...
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1answer
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How do I make OS X set the terminal title back to the original title when coming back from ssh?

Starting on OS X, I ssh into foo (a Linux box). My terminal title changes to foo. I then ssh into bar (another Linux box). My terminal title changes to bar. I log out of bar. My terminal title ...
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3answers
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TortoiseSVN overlay icons do not appear when installed by a different user account?

I've installed TortoiseSVN on my work Windows XP machine as the administrator. When I login in as a standard user my working copies do not display the overlay icons in Windows Explorer. I found this ...
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4answers
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BASH history truncated to 500 lines on each login

For some reason, I cannot get my system to keep my BASH history after a reboot. Here are the relevant sections of my ~/.bashrc: shopt -s histappend PROMPT_COMMAND='history -a; updateWindowTitle' ...
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1answer
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Is there a way of using ctrl-r after typing part of command in bash?

In bash the Ctrl+r command is very useful, I type Ctrl+r whatever and it searchs my history for commands containing the word whatever. But if I type whatever and realize that I would like search that ...
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7answers
8k views

Screen Capture - command line?

Is there a command line tool out there that can record your computer screen and audio device and then save that to a file?
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3answers
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Windows & Git Bash: Bash PATH to read Windows %PATH% system variable

I've recently added a directory to the Windows PATH manually by going into Control Panel -> System -> Advanced system settings -> Environment Variables -> User variables -> PATH. (Windows 7, 64-bit.) ...
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2answers
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How to cut a file to a given size under Linux?

I want to shrink a file's size by brute-force, that is, I don't care about the rest, I just want to cut the file, say by half, and discard the rest. The first thing that comes to mind is Perl's ...
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6answers
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What's the difference between the terms “Shell” and “Bash”?

What is the the difference between "Shell" and "Bash" and what do these terms mean? As far as I know, there is no difference. But I've seen many books about "Shell" and others about "Bash"! So in ...
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5answers
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How do you get a shell on a Mac?

I have never used a Mac before. I recently went to an Apple store and tried to open a shell to try it out. But, I was not able to open a shell - no shortcut for it, not right-click-menu entry, nothing....
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What's the difference between filename and ./filename in Linux

What is the difference between filename and ./filename? Under what circumstances is one preferred to the other?
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how can i install CentOS 6 without the gui?

i just downloaded the centos 6 live cd and i tried installing it on virtually and i am never prompted to install centos with/without gui and its all automated. what happends is after i am booted into ...
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2answers
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Bash not loading '.profile' in new session on Linux

I'm setting up a new Linux machine I got from our IT dept, and noticed .profile is not loaded when I start a new terminal session. The current shell is Bash, though I changed it from the default sh it ...
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8answers
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Mass renaming, *nix version

I was looking for a way to rename a huge number of similarly-named files, much like this one (a Windows-related question) except that I'm using *nix (Ubuntu and FreeBSD, separately). Just to sum up, ...
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2answers
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Execute command after seconds (without sleep)

How can I run a command after X seconds without sleep. Or with sleep but without the shell just wait for the response of that command? I used this but it didn't work sleep 5 ; ls > a.txt I need ...
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2answers
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how to set ENV variable in windows CMD line

I'd like to set a temporary enviroment variable in windows CMD line, which in my word the windows shell. because it's for temporary usage, So I don't want to add a new enviroment variable system wise ...
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3answers
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Is there a shell which supports fuzzy completion as in Sublime Text?

I'm using bash and I was wondering if there is any plugin in bash or other shell which allows me to do this cat tfnislong.txt + [tab] completes to cat ThisFileNameIsSoLong.txt just like tab completion ...
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2answers
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Shell script echo new line to file

I want to echo a new line to a file in between variables in a shell script. Here's my code: var1="Hello" var2="World!" logwrite="$var1 [Here's where I want to insert a new line] $var2 echo "$...
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3answers
711 views

Figure out what non-symlink path would be?

On Linux, if I've cd'd around and am now in a directory, is there a way to figure out what the real path to that directory is if I had not used a symbolic link to get there? Consider: $ pwd /home/...
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1answer
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why doesn't a bash while loop exit when piping to terminated subcommand?

Why doesn't the command below exit? Rather than exit, the loop runs indefinitely. While I discovered this behavior using a more complex setup, the simplest form of the command reduces to the ...
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2answers
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What is the difference between /etc/environment and /etc/profile?

I understand that the former is loaded prior to the latter, but what is the conceptual difference? Are there any good reasons I should set some variables in one and not in other? Except the fact that /...
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2answers
377 views

How to move folder in unix using mv, only when target is on the same drive

I need to move a folder using unix mv command, but only if the target is in the same drive or the same filesystem. What would be the best approach?
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1answer
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PowerShell vs. the Unix Shell

I've heard some things about the features of the PowerShell. Some of it seems like typical features of Unix shells. So it seems Powershell includes piping and the commandlets, similar to shell ...
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2answers
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Making bash TAB completion more like cmd.exe [duplicate]

I wondered if theres a way to do rotational style completion in bash similar to the behavoir on cmd.exe, I've found it speeds me up in regard to entering commands
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1answer
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HOSTNAME environment variable on Linux

On my Linux box (Gentoo Linux 2.6.31 to be specific) I have noticed that the HOSTNAME environment variable is available in my shell, but not in scripts. For example, $ echo $HOSTNAME returns ...
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7answers
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re-use '~/.profile` for Fish?

(I'm talking about the shell Fish, esp. Fish's Fish.) For Bash/ZSH, I had ~/.profile with some exports, aliases and other stuff. I don't want to have a separate config for environment variables for ...
10
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2answers
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How can I tell if OS X is connected to a VPN network from the command line?

How can I tell if OS X is connected to a VPN network from the command line? By running ifconfig without any arguments when I am connected, I see that there is a utun0 interface which appears to be ...
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votes
6answers
16k views

Linux command to find files changed in last n seconds.

I would like a Linux command to find files changed in last n seconds. Is there a shell script or other tool that I can run from command line interface or gui?
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3answers
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How do I set my shell in Mac OS X?

I know I can set "Shells open with" in the Terminal preferences, but I'm curious if there's any system-wide way of setting this (similar to updating /etc/passwd in some Unixes).
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3answers
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How to delete files on the command line with regular expressions?

Lets say I have 20 files named FOOXX, where XX is the number of the file, eg 01, 02 etc. At the moment, if I want to delete all files lower than the number 10, this is easy and I just use a wildcard, ...
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3answers
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Why doesn't '>' redirect error messages from gcc?

I stored the following program in new.c int main() { a; return 0; } It returns an error message. I want to send this message to a file. So I used the following command gcc new.c > ...
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6answers
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Clear stdin before reading

I have the following bash script: # do some time consuming task here read -p "Give me some input: " input Now as you might have guessed, if a user presses some random keys during the "time ...
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4answers
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Parallel shell loops

I want to process many files and since I've here a bunch of cores I want to do it in parallel: for i in *.myfiles; do do_something $i `derived_params $i` other_params; done I know of a Makefile ...
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4answers
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Bash Shell Tutorials [closed]

What are some good bash tutorials? I would like to learn more about the bash shells commands and how to use them.
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1answer
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When using “gzip --decompress”, the result is “gzip: MYFILE.zip: unknown suffix — ignored” on Windows

In Windows PowerShell (if it matters), I would like to decompress a zip file with gzip with the argument --decompress, but unfortunately it doesn't work. Please look at the screenshot below. gzip --...