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

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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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how to `tail` the latest file in a directory

In shell, how can I tail the latest file created in a directory?
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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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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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How can I sort all files by size in a directory?

How can I display the files in a unix directory sorted by their human readable size, going from largest to smallest? I tried du -h | sort -V -k 1 but it does not seem to work.
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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 -> ...
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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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680 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 ...
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Is there any functional-like unix shell?

I'm (really) newbie to functional programming (in fact only had contact with it using python) but seems to be a good approach for some list-intensive tasks in a shell environment. I'd love to do ...
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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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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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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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tee for Windows?

Does Windows provide the basic tee facility for copying standard input to an arbitrary set of files and then back out to standard output? I generally download a generic tee program, but curious if ...
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Run a GUI app on remote computer from SSH

I want to run a GUI application on my Ubuntu computer, but it should started by a shell script on my Debian server trought SSH. Is this possible?
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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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9answers
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Linux & Shell - Is Shell a must?

A total newbie question. Why do we need a shell in Linux? As an example when I type - find . -name xy* - I was told that the shell takes this input and calls the find command (making sure the wild ...
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Ending a process in unix instead of interrupting it

At the unix command line if i press Ctrl-C,that does not end a process but rather interrupts it and i return to the shell prompt. So,i have the following two questions: 1.Is there a way i can see the ...
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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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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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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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unix - split a huge .gz file by line

I'm sure someone has had the below need, what is a quick way of splitting a huge .gz file by line? The underlying text file has 120million rows. I don't have enough disk space to gunzip the entire ...
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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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Will a Mac help me learn Linux?

I worked with a Mac last week for the first time ever. I noticed that the shell is very similar to Linux. I normally develop on a Windows machine and tend to be a noob at all things Linux. Will a Mac ...
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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 ...
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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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1answer
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Retrieve Linux command line history by date

I want to see what I typed on my bash command line on a certain day a week ago. Is there a way to retrieve command line history? Something like below, perhaps? > history --include-date | grep ...
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Using wildcards in commands with zsh

Using commands such as rsync and scp with ZSH I've run into trouble. Instead of the (normal) behaviour of giving me all matching files, it won't run and returns: ➜ ~ rsync -azP user@server:~/* ~/ ...
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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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How can I kill Firefox by console?

I know I can type: ps -A | grep firefox I get something like: 6818 ? 00:04:23 firefox Now I can kill it by means of: kill -9 6818 How can it be done in one command and how can I make ...
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Run a shell script with an html button

I want to launch a bash script when a button is pressed on a website. This is my first attempt: <button type="button" onclick="/path/to/name.sh">Click Me!</button> But no luck. Any ...
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2answers
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Can I keep . and .. out of .* expansion?

I often find it annoying (or worse) when I type command .* in bash and the command applies to the parent directory and current directory. Is there some shell option or other configuration I can ...
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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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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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How to change proxy setting using Command line in Mac OS?

I am using Mac OS and sometimes some work need to be done using a proxy so I need to change my proxy setting frequently. But changing proxy setting in System Preferences is very messy. Is there a ...
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Is it possible to modify bash to run one command through another (say a python script)?

I was wondering if it is possible to modify bash such that when I type command --arg1 what actually happens is ~/prerun.py command --arg1 (prerun.py would handle starting command --arg1 itself) ...
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How do I combine stdout and stderr for different shells?

I know the answer for some shells, e.g. with cmd.exe you can: some.exe > out.txt 2>&1 How do you achieve the same for other shells (bash, ksh, tcsh, powershell, etc)?
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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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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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UNIX shell scripting: how to recursively move files up one directory?

I have a large number of small files, f, arranged in a directory structure like so: /A/B/C/f There are 11 directories at the level of A, each with about 100 directories at the level of B, each with ...
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How can I keep the color when I run the external command inside vim?

For example, for the command ls --color displays colorful results when being executed in the shell. However, when I call :!ls --color inside vim, all color information is gone. What should I do to ...
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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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1answer
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What do these cryptic strings really mean in registry associations?

Looking at my HKEY_CLASSES_ROOT\Word.Document.12\shell\Open\command\command value (Word 2010 'Open' shell association) I see this sort of nonsense: ...
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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 ...
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Per-directory bash/zsh history log files

I find I do a lot of work on a project in a set directory. Sometimes — a few months down the track — I need to redo something on that project but I can't remember what I did. I use ...
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Is it possible to configure the way bash completes directory names?

I'd like to instruct bash to use a special method to perform completion on certain directory names. For example, bash would call a program of mine to perform completion if a path starts with "$$", and ...
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3answers
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Windows 7 coming from Linux/Unix?

I've got a Windows 7 box going for my job, and most high-level computing experience is coming from shell environments in Linux. I'm completely lost in the Windows shell, and when I try to use a GUI ...
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3answers
429 views

Tabbed terminal that connects to a GNU Screen session?

I use the session feature of screen extensively. For example, I'll start a screen session for "project1" as "screen -S project1", and then when I need to reconnect I use "screen -d -r project1". ...
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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, ...
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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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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 > ...