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

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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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4answers
7k views

Is there a way to edit files inside of a zip file without explicitly extracting them first?

I sometimes need to make changes to a .zip or .jar file, so I usually move the file to /tmp, extract all the files with unzip, edit a few files, and then re-zip up the files. This works, but it can ...
9
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1answer
4k views

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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1answer
5k views

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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7answers
14k views

How can I list only non-empty files using ls?

How can I list (using ls) all files that are not empty (size > 0) using linux?
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6answers
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Best practices to alias the rm command and make it safer

Some time ago I erroneously deleted my home folder because I ran a rm -rf * on the wrong terminal, whose working directory was the home folder! I wish I had an alias for the rm command, but it was ...
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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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4answers
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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
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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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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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5answers
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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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3answers
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How to display current path in command prompt in linux's sh (not bash)?

I would like to display current path in sh prompt (not bash shell), which currently just shows "#", I tried with introducing this env PS1="$(whoami)@$(hostname):$(pwd)" and set ...
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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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3answers
870 views

`which python` points to the python I want, but `python` runs the wrong version

I want to use python24 provided by ports, so I've installed it, and python_select -s shows that the version I want is indeed selected. Running which python gives /opt/local/bin/python, and running ...
8
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1answer
14k views

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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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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7answers
789 views

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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2answers
503 views

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 ...
8
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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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2answers
2k views

Writing shell scripts that will run on any shell (using multiple shebang lines?)

I've just started getting deeper into shell scripting, and I've always just thrown my script in a file, marked it chmod +x and then done /path/to/script.sh and let whatever interpreter is the default ...
8
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1answer
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ZSH tab completion of git commands is very slow. How can I turn it off?

If I type: rm <TAB> I'll see possible completions almost instantly. However, if I type: git rm <TAB> It'll hang for several seconds if it's in a git repo, or fail to show any ...
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2answers
882 views

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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4answers
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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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7answers
6k 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
1k views

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 ...
8
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1answer
240 views

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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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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8answers
834 views

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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votes
3answers
365 views

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
8k views

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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3answers
160 views

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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2answers
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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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3answers
410 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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6answers
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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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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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8answers
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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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2answers
744 views

How do I delete a file named “-p” from bash?

How do I delete a file named -p in bash? Trying rm "-p" complains that -p is not a valid argument.
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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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4answers
280 views

What to use for Shell Access? [closed]

I just purchased a virtual dedicated server-plan that comes with shell access. It's been a while since I've actually used shell access remotely, so I'm a bit behind the times. Years ago I used PuTTY, ...
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3answers
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How to join files on the command line without creating temp files?

I have two files in a Linux / Bash environment: # Example data $ cat abc 2 a 1 b 3 c $ cat bcd 5 c 2 b 1 d I'm trying to join the two files on the first column. ...
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8answers
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How to find out the top space-consuming directories or files?

My disk is running out of space: $ df -h Filesystem Size Used Avail Use% Mounted on ... /dev/sda7 803G 715G 48G 95% /home I'd like to go through the whole home directory and find ...
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1answer
9k views

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 ...
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4answers
17k views

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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4answers
471 views

Documenting Unix commands on the command line

I would like to append both the last command and the output of the last command to a text file for the purpose of a tutorial. For example: After I do an ls in my home directory I see this on the ...
7
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5answers
8k views

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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votes
2answers
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Smart tab completion (for directories)?

Are there shell versions that have a more intelligent tab completion? I'd like to be able to type cd foo-<TAB> Then it would show me the possible completions along with numbers that I can ...
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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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3answers
497 views

Why I have to type “./” always before an executable to execute it in Linux?

When I compile e.g. x.c by: GCC x.c -o x To execute result I have to write: ./x And just typing: x Fails with this message: x: command not found This means Linux does not search current ...
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1answer
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Awk doesn't work when inside double quotes

This command doesn't work: ssh $HOST "ls -l | awk '{print $1}'" Above ignores the command "awk" I think it might be because of the double quotes? Also, how would I add another set of double quotes ...