A shell script is a script written for the shell, or command line interpreter, of an operating system.

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Is #!/bin/sh read by the interpreter?

In bash or sh, I guess anything which starts with # is a comment. But in bash scripts we write: #!/bin/bash And in Python scripts, there is: #!/bin/python Does this mean that # by itself is a ...
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Can I make the webcam take a picture when an incorrect password is entered?

I am using a laptop . I was thinking to have a support in my Ubuntu machine. When an incorrect password is entered, a picture is taken later revealing who has been trying to gain access. I have ...
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What is the difference between ./ and sh to run a script?

I have written a simple script. When I runsh <myscriptname.sh>, i got the correct output, but when I run ./<myscriptname.sh>, I got an error. What is difference between when I do sh and ...
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How can I determine whether a shellscript runs as root or not? [duplicate]

Possible Duplicate: How can a script check if it’s being run as root? This is something I've been curious about. I make a lot of small bash scripts (.sh files) to do tasks that I routinely ...
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How can I get a list of all repositories and PPAs from the command line?

I know how to list all packages installed on my system. But how could I get a list of all repositories and PPA's? I know I can look into /etc/apt/sources.list and /etc/apt/sources.list.d, but I'm ...
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How do I create a deb package for a single python script?

I have a single python script that I want to distribute as a deb package. It is a indicator which shows local date in Unity panel. I did follow create a .deb Package from scripts or binaries but I ...
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What is the difference between “source” and “.” in bash?

As the question says, what is the difference between executing a script with source command and with . , i.e.: source /some/script and . /some/script
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Differences between /bin, /sbin, /usr/bin, /usr/sbin, /usr/local/bin, /usr/local/sbin [duplicate]

I'm running an Ubuntu Server 13.04, but I see the same on a 12.04: I have six directories with command files. These are: /bin /sbin /usr/bin /usr/sbin /usr/local/bin /usr/local/sbin What are the ...
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bashrc or bash_profile?

I know the difference between the two bash login scripts: .bashrc is run only by "non-login" shells. .bash_profile (or .bash_login or .profile) is executed by "login" shells. Does anyone have some ...
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What is difference between /bin/sh and /bin/bash?

if I write, #!/bin/bash echo "foo" or #!/bin/sh echo "foo" both yields same. I have seen some scripts starting with #!/bin/sh or #!/bin/bash. Is there any difference between them?
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How to make Skype use notify-osd?

How do I make Skype use the default Ubuntu notify-osd to display notifications (incoming messages, users connecting, etc.) instead of the Skype's own "ugly" message box?
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Bash remove first and last characters from a string

I have a string like that: |abcdefg| And i want to get a new string called in someway (like string2) with the original string without the two | at the start and at the end of it so that i will ...
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How to keep “dot files” under version control?

Etckeeper is a great tool for keeping track of changes to your configuration files in /etc A few key things about it really stand out. It can be used with a wide variety of VCSs: git, mercurial, ...
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ssh: automatically accept keys

I've written this small utility script: for h in $SERVER_LIST; do ssh $h "uptime"; done When a new server is added to $SERVER_LIST, the script is stopped with: The authenticity of host ...
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'chmod u+x' versus 'chmod +x'

What is the difference between chmod u+x and just chmod +x? I have seen a ton of tutorials that say to use u+x to make scripts executable. However, the u is not mentioned in the chmod help or ...
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How to install an init.d script in ubuntu?

I am trying to install an init.d script, to run celery for scheduling tasks. Here is the steps I followed: copied the file celeryd and pasted it in folder /etc/init.d/ created a configuration file ...
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How to add a shell script to launcher as shortcut [duplicate]

Possible Duplicate: How can I edit/create new launcher items in Unity by hand? How can I create launchers on my desktop? I want to add some shell scripts in my launcher as shortcuts.. ...
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Beep in shell script not working?

I'd like to use a beep sound in a shell script. Unfortunately none of the methods I found via Google work for me. I tried echo -e '\a' echo -ne '\007' and the command beep after I installed it ...
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How can I create a select menu in a shell script? [closed]

I'm creating a simple bash script and I want to create a select menu in it, like this: ./script echo "Choose your option:" 1) Option 1 2) Option 2 3) Option 3 4) Quit And according to user's ...
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How to execute a script just by double clicking like .EXE files in Windows?

How can I make a bash script executable by double clicking just like .exe files in Windows? I tried creating a launcher and assigning the script to it, but there are two consequences: the terminal ...
17
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1answer
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how to execute a command after resume from suspend?

I've got a script that is executed in order to have suspending/resuming working in my laptop. Then I have another series of xinput,xkbset and xmodmap commands that are executed when I initiate a ...
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Execute script before shutting down

When I shut down my computer I want to show some pending tasks that I have to do before leaving the office... I did a local application to manage those tasks, basically I just want to run a command, ...
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How can I initiate Nautilus file operations from the command line?

How can I start Nautilus's "File Operations" GUI from the command line? My goal is to include this in a Nautilus script.
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Command to convert an upper-case string to lower-case?

What is the Bash command I can use to convert an upper-case string to lower-case and vice-versa? Thank you.
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How can I make a script that opens terminal windows and executes commands in them?

I have three scripts I need to run when I start up my Ubuntu machine, they start services I use in my development environment. To do that, I manually open three terminals and type in the commands. ...
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How can a script check if it's being run as root?

I'm writing a simple bash script, but I need it to check whether it's being run as root or not. I know there's probably a very simple way to do that, but I have no idea how. Just to be clear: What's ...
15
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1answer
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Command to append line to a text file without opening an editor

Assuming i have a line that i want to add to a file without opening an editor. How could i append this line alias list='ls -cl --group-directories-first' to this file config.fish
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How can I find the location (on the desktop) of a window on the command line?

I'm trying to write a little script to help manage my windows via keyboard shortcuts. In order to do what I want, I need to be able to find the current location and size of the "active" (focused) ...
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How to run an alias in a shell script?

I have an executable file mpiexec, whose full path is ~/petsc-3.2-p6/petsc-arch/bin/mpiexec. Since I want to execute this command in different directories (without having to retype the entire path), ...
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How to determine if a string is a substring of another in bash?

I want to see if a string is inside a portion of another string. e.g.: 'ab' in 'abc' -> true 'ab' in 'bcd' -> false How can I do this in a conditional of a bash script?
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How do I tell a start up program to start minimized?

Here is a quesion that has been bugging me. You know how you can set up a program to run on start up right? Well, how can i tell it to start minimized, like you would do in windows? TeamViewer ...
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How To Get Plymouth To Display Boot Messages When Booting?

I would like to know how to create a splash for Ubuntu Maverick with boot messages being displayed when I boot as well as a progress bar and a spinning logo. Or, if possible, how to edit a splash ...
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Record a programs output with PulseAudio

I would like to record an output of a program with PulseAudio using command line/bash script. It is important not to record every output of the sound card, but only the one of one specific program. I ...
14
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2answers
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How can I write Nautilus scripts in Python?

I want to write a Nautilus script in Python. Is that possible? If it is possible, how can I do that?
13
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At what time does cron execute daily scripts?

If I place a shell script in /etc/cron.daily/, at what time of the day will it be executed?
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How to start a terminal with certain text already input on the command-line?

Rather than rephrasing my question, let me describe to you the desired user-case: I create a short shell-script to run command "gnome-terminal --someoptionflagname 'my text to be posted'", and ...
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1answer
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How to run a shell script when a new USB storage device is detected?

I want a script that dumps the log and starts logging on it as soon as a usb mass storage is plugged (with the file 'OKdump' on it).And if anything abnormal(Like a error that is visually present) is ...
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Showing a “cowsay” fortune in every new terminal session

I wish to display a cowsay message in every terminal window. The command I use is fortune | cowsay Any ideas how to make it appear whenever I start a new terminal session?
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What is apt-fast and should I use it?

Several times over the past couple years, I've heard of people using apt-fast for updating and installing packages, but I'm not really sure what it does. I think I've traced its origin to this forum ...
12
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How can I make “rc.local” run on startup?

I have a script that I would like to run when my system starts. I have put it on "rc.local", but it doesn't work. How can I enable it to run on startup? Thanks!
11
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How to run scripts every 5 seconds using cron?

I would like to know how to run a script every 5 second. I know that cron can do every minute. How do you get intervals below that?
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How to remove Change Desktop Background from right click?

I want to restrict users on changing wallpapers and themes. So can anyone say me how to remove Change Desktop Background option from right click? Note: I just totally want to remove that option ...
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Script to display all terminal colors

Throughout the internet I have seen many people with scripts that prints out a bunch of stuff in all the colors defined in ~/.Xdefaults. However when I try to use these, I always get error: Bad ...
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Upstart script doesn't start

Ubuntu 10.04 I have created this upstart script (/etc/init/pure-ftpd.conf): # pure-ftpd - FTP server description "Pure-FTPd server" start on filesystem stop on runlevel S respawn respawn limit ...
11
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2answers
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How do I run a script after OpenVPN has connected successfully?

How can I associate a script to OpenVPN so that it runs when the VPN is connected successfully?
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How can I programmatically change a file's icon?

If I select an icon in Nautilus and select Properties, I can click on the icon presented there. This gives me a file-chooser dialog to select a new icon image. I would like to do this via a script of ...
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What language(s) can I use in LibreOffice for macro scripting?

Not finding any info online; I hope somebody here knows. It was Python in OpenOffice; is it still Python? Or are they moving to gasp VBA?
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How can I preserve the executable bit on a file that is synchronized by Ubuntu One?

A script I am working on is in a folder that is synchronized by Ubuntu One. Every time I edit it from another computer, it looses its executable bit and I must manually reapply chmod +x. How can I ...
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Not able to execute a .sh file: /bin/bash^M: bad interpreter

I wanted to execute a shell script: -rwxr-x--x 1 root root 17234 Jun 6 18:31 create_mgw_3shelf_6xIPNI1P.sh I tried to do a standard procedure, but I am got this error: ...
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What is the least insecure way to store a password that is used by a script?

I have a Bash script that automatically authenticates with a service using my username and password. The credentials are currently stored as plain text within the script. What precautions should I ...