Bash is the shell used in Ubuntu's command-line interface.

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Difference between cd / and cd //? [duplicate]

What is the difference between cd / and cd //? We can see that adding / to the end doesn't do anything. But when I do cd // and pwd, I found: $ cd // $ pwd // What is difference between / and ...
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4answers
260 views

Explain exec in simple terms?

I don't understand the bash command exec. I have seen it used inside scripts to redirect all output to a file (see ...
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1answer
162 views

How to quickly check the value of bash variables, aliases and history commands from terminal?

How do you expand in place: bash aliases environment variables history commands to edit them and check they are correct? For example, I have some aliases I use for flashing different devices and ...
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2answers
865 views

Creating a new subdirectory in multiple existing directories

I am trying to figure out an elegant way to create a new subdirectory in a series of existing directories. I have 15 already created directories called Week1 through Week15. Within those ...
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2answers
1k views

Pass variable value to script from terminal

I like the shred command so instead of using the 'rm' command I prefer shred. I would like to create a bash script in /usr/bin, say we will call it "shredder" so that if I want to shred a file (i.e. ...
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0answers
36 views

“sudo !!” doesn't give me permissions. What am I missing? [duplicate]

When you forgot to sudo a command you may want to write, sudo !! That would execute the last command applying the sudo command to it. However sometimes seems I can't do that, for example inside ...
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5answers
2k views

How can I run original command that aliased with same name?

An alias for ls command in ~/.bashrc file aliased with this one: alias ls='ls --color=auto' then, when I run ls command in terminal aliased ls(ls --color=auto) runs. but my question is how can I ...
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1answer
2k views

Crontab not executing jobs Ubuntu 14.04

I am trying to run bash script as a cron job every 15 minutes. The bash script simple calls a Java program. I made an entry in crontab to run the file every 15 minutes and saved it but it would not ...
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2answers
1k views

Hide stdout of a process only when it is running in background

How could I hide the standard output of a process only when it is running in background? For example, test.sh #!/bin/bash for i in $(seq 200); do echo $i done Now, I run the script. I stop ...
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1answer
305 views

CPU performance on sleep command

This is rather a beginner question. I wonder what happens when sleep command is triggered from a bash script, for example. That job would still running, with less priority?
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0answers
50 views

Diffrence beetween ' and " in bash [duplicate]

Please bear with my stupid question. I want to know the difference between ' and " in bash. Please explain it to me with an example.
0
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1answer
329 views

How to let bash script knows if the open terminal is closed or not

I want to write piece of bash script that open a gnome-terminal tab and execute some commands in it after finishing execution terminal will close , i would like the make bash recognize if this ...
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3answers
591 views

Not able to run sed on bash script

I am working trough some legacy code which does not work, I came across a part that is causing problems. I was hoping some one could help me out and fill me in on what is the exact functionality of ...
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2answers
156 views

Bash script special character and background job bug

gnome-terminal --tab -e " sh -c ' gedit'/media/ubuntuman/Onces And for Al/scripts/faceBook' & ; sudo cpulimit -e ubuntu-tweak -l 80;'" This is the piece of code I want to edit. The special ...
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4answers
1k views

Creating a symbolic link to a directory

I have a directory to which I want to create a symbolic link. The commands I used were: cd workspace_b4a cd android-sdk-linux ln -sv build-tools/20.0.0/lib/ platform-tools/lib The output was: ...
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1answer
161 views

Can't trap (Ctrl^C) in my simple script

I don't know why I can't trap Ctrl^C in this simple script. #!/bin/bash for number in $(seq 10); do echo -n "." sleep 2 done function finish() { echo "bye." } trap finish ...
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1answer
947 views

Can't Change power_method 14.04

I am trying to modify my power method for my ati card as it's like having a helicopter in the room. I use the same methods described here. sudo bash -c echo "profile" > ...
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1answer
725 views

bash: /etc/bash.bashrc: Permission denied I have no name!@lappyname:~$

During resolving another problem I run this command : pkexec chmod 0440 /etc/sudoers pkexec chmod 0440 /etc/sudoers.d/README mount -o remount,rw / Than after error occurs and after reopen the ...
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2answers
638 views

Reset History inside a bash script [duplicate]

I want to make a bash script that clears the history i.e. works similarly as the command history -c So I started with the following code:- #!/bin/bash history #displaying history history -c ...
2
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2answers
280 views

Error using “cp” to copy files to an external disk

I have a 2TB external HDD formatted with exFat that I use to share very large files (>10GB) among Ubuntu, Windows 7 and MacOS. I am trying to copy the whole content of a directory using sudo cp -r . ...
0
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1answer
98 views

Path to shell script in aliases with ./

I'm trying to make an alias for my shell script which is saved in ~/Dokumente/music.sh Therefore, I added following line to ~/.bash_aliases: alias music='.//home/robin/Dokumente/music.sh' After ...
1
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2answers
537 views

exports in .bashrc not working

I have a program .path.py which prints an export command for PATH. In my .bashrc I have an entry at the top $(python $HOME/.prefix/.path.py) except that when I login over ssh, or even run source ...
2
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1answer
768 views

fsl.sh cannot be sourced

I need to install FSL and Freesurfer as part of running Connectome Mapper. Freesurfer required changing the shell to tcsh in order to configure its folders. Now for FSL, I have to add to .profile the ...
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2answers
890 views

How to run .sh through terminal without using Nautilus Ubuntu 14.04 [duplicate]

I have an .sh file that looks like #!bin/bash exec /usr/lib/jvm/java-7-openjdk-amd64/jre/bin/ java java -jar /home/me/myfolder/my.jar I've made this file executable and it works fine when in the ...
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2answers
150 views

How to write a script with nautilus actions?

I want to use nautilus actions with my own script which I have usually started successfully with open-terminal and pasting the command (s. below) directly in the terminal. for file in *.mp4; do mkdir ...
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3answers
1k views

How to differentiate command from the output using color

I have to differentiate command from the output using color like this $ cat file-name (this should be in some color say like red) some test in file OUTPUT (this output should be in some other color ...
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2answers
480 views

I think I deleted bash!

I am attempting to make a PXE server that will boot Ubuntu (live cd) 14.04. I was trying to copy the bash file from /bin/bash to /var/lib/tftpboot/Ubuntu/bin/bash I must have used the ...
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2answers
265 views

How to properly detach a command?

I have this little script I use to launch a root Nautilus window (yeah, dangerous, but sometimes necessary): #!/bin/bash gksudo --description "Launch a root Nautilus" -- sh -c "xdg-open / &" ...
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1answer
1k views

Undo apt-get remove --purge

I wanted a fresh install of Python and ran sudo apt-get remove --purge python. Apparently it has killed almost everything I had installed in my system. Looking at the history.log I guess I could ...
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3answers
232 views

Cannot find location of permanent aliases.

A couple of months ago, I made a few permanent aliases for my bash shell on Ubuntu 14.04. They are actively making my life easier, and I would like to add a couple more to the list, but I cannot find ...
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2answers
20k views

How to send an email using command line?

Here's what I have: cat UserReport.txt | mail -s "TestSubject" "nospam@gmail.com" It's a small file, much smaller than a picture so it should send almost instantly. Though I receive nothing. I ...
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1answer
295 views

How to run bootinfoscript from the GParted liveCD?

How to run bootinfoscript from the GParted live CD? Windows 7 on internal hard drive, and Linux on an external USB SSD drive (Linux not loaded).
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7answers
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How to make the argument as optional in bash?

In below function with 9 arguments: SUM() { echo "The sum is $(($1+$2+$3+$4+$5+$6+$7+$8+$9))" } I want to make the second arguments to the next(3..9) become a optional arguments. When I call ...
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1answer
212 views

Sourcing a file [closed]

I am using ROS (Robot Operating System www.ros.org). I have to source .sh file every time. What it means ? source /opt/ros//setup.bash or have to enter this line in .bashrc file Why we need this ?
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4answers
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making a bash script executable programatically

I need to create a bash script to create and mount a drive. So, two simple commands. Both "work" when entered at the command line. The script is created and executed every time a normal user logs in, ...
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3answers
406 views

Special variables in bash

I know these are few special variable used by bash. But I am not able to understand it. Can anyone explain me what are these variable and how to use it? $* $@ $#
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1answer
148 views

Shell Script Problem

I decided to make a shell script for basic nmap scanning so I did it like this : #!/bin/bash sudo apt-get install nmap printf "enter the name of site to do basic scan on >>>" read NAME ...
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3answers
106 views

Wildcard: return source path

I'm trying to rename every access.log.gz file (note: exact filename, not "beginning with" or "containing") found in /home/*/logs to date-access.log.gz in the same folder. for file in ...
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2answers
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Bash error on opening the terminal

Whenever I open terminal in Ubuntu I get the following bash and I don't know how to solve it. I need a solution as soon as possible: bash: ...
2
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1answer
17k views

“Syntax error: Unterminated quoted string”

I am trying to use a backup script that will backup my sql database and website files. I am running Ubuntu 12.04 32 bit version and zPanel. Here is what my DB structure is along with which DB I want ...
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1answer
476 views

Bash script for multiple tabs program running

I have the following bash script code to open multiple session of a python script with different input argument in different terminal tabs. #!/bin/bash cd /home/me/experiment tab=" ...
2
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0answers
379 views

Shell command not asking for password inside while loop [closed]

I am trying to run .sh file to put certificate via keytool command in every jre/lib/security/cacert file described in ~/.java/deployment/deployment.properties file. #!/bin/bash ...
2
votes
1answer
1k views

Bash script that opens multiple netcat instances and exits them

I am trying to create a script that opens up multiple gnome-terminals and opens a netcat connection. After a couple seconds I would like the terminals to close. I am at a loss and I believe it can't ...
0
votes
1answer
65 views

combine multible commands in one run one of them is find

I want in one line a command to use find to get a file name from a txt file , search for it , and play it then after closing the video I need to run a certain script I managed the first part but ...
1
vote
1answer
982 views

Why won't this php script execute bash script?

Why am I not able to execute this bash script using php? I have tried exec() as well as shell_exec(). index.php <?php $old = getcwd(); echo $old; chdir($old); $message=exec("a.sh"); ...
0
votes
2answers
278 views

gnome-terminal profile without bash history

I'm trying to create a profile in gnome-terminal that doesn't store bash history. The easiest way to do that is to run export HISTIGNORE="*", but there is one problem, gome-terminal is executing ...
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2answers
2k views

Why isn't one 'bash' command working at startup

I am working on a VM with Lubuntu 14.04, I have created a script a.sh, #!bin/bash echo "aaaa" >> a.txt And my /etc/rc.local file is as follows: #!/bin/sh -e # # rc.local # # This script is ...
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4answers
113 views

How to arrange this file properly?

I'd prefer to edit TestFile in place to get the desired output. How could I do this? This is a work box so I'd prefer to not have to install additional packages. TestFile: randomcollege-nt\jsmith90 ...
5
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3answers
32k views

How to kill a script running in terminal, without closing terminal (Ctrl + C doesn't work)?

I have written a bash script that calls several other programs and executes a bunch of commands. I run this script from the terminal. Now I want to kill the script. Pressing Ctrl + C sometimes ...
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1answer
536 views

Run pkill without sudo permission

I want to run pkill like below. sudo pkill -u 11002 I cannot give sudo password multiple times, so I want to run pkill without sudo user. For this i copied pkill to home as named bkill, and then i ...