Questions about bash only, as opposed to other Bourne/POSIX shells. For all Bourne/POSIX-style shells, use the /shell tag instead.

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-1
votes
0answers
5 views

placing things in a users home directory with .deb

i am making a .deb installer and would like to place some files in the users home directory but i can not hard code a username. does any one know of any other places in the file system that i could ...
3
votes
2answers
37 views

The output I get via “echo” works as a command when pasted to terminal, but not in the script

I'm trying to change the files generated by an app that unfortunately often contain spaces. I have managed to get "echo" to give me output that works if copy pasted into terminal, but when I try to do ...
0
votes
1answer
22 views

finding and replacing text [duplicate]

Does any one know how to find and replace text in a file. it can be implimented into a bash file. i would like to find the line and the output the text to it the file can only be opened with the root ...
4
votes
4answers
5k views

Bash Auto-Completion feature for SSHing into Different Hosts

I have big list of servers which I normally ssh to all the time. Is there any way using bash or zsh so that I can keep the list of hostname and bash auto-completion goes through the file and gives me ...
4
votes
3answers
1k views

Autocomplete server names for SSH and SCP

I have a few servers configured in ~/.ssh/config, such as alpha and beta. How might I configure Bash such that the commands ssh al<tab> and scp file.tgz al<tab> autocomplete the names of ...
0
votes
0answers
9 views

bash/svn how to filter documents [on hold]

Does anyone know how to filter documents. For example, if I had something like this: dVa/Prs/Upe/dVar.var I want to only the last file in log and then add to this file another for example after ...
0
votes
1answer
12 views

Unix: Looking to run a script in directories with a certain name

I am writing a script in bash. If I am in directory Foo, I want to run this script in only the subdirectories of foo that are named foo with up to three numbers after foo. Ex: foo1, foo23, foo345 ...
2
votes
1answer
38 views

Bash: command substitution with multiple unset/export commands

I am trying to unset some variables and export others using command substitution. This works: $(echo " export TEST_A=1 export TEST_B=2 ") And this too: $(echo " unset TEST_A ...
3
votes
1answer
41 views

Can I run a command loaded from .bashrc with sudo?

I have some custom functions and aliases defined in my .bashrc file. Sometimes I need to execute whem as root. I then do something like: $ sudo custom_cmd 80 ...
0
votes
2answers
22 views

Command substitution and spaces

Why does this work as a calculator: [root@qabun02 ~]# echo $(( 5+2 )) 7 but this doesn't? [root@qabun02 ~]# echo $( (5+2) ) -bash: 5+2: command not found The only difference I can see is the ...
0
votes
1answer
28 views

Special characters in bash script w/sed

I am running a script to check my gmail from the command line and display the first 35 characters in the title. curl -u username:password --silent "https://mail.google.com/mail/feed/atom" | \ grep ...
1
vote
1answer
66 views

Why does the printf statement in this loop output the array out of sequence?

When I execute the following code, the output of the printf statement appears to show array out of sequence. In the declare statement the Source item is declared before Destination and in the output ...
0
votes
2answers
50 views

How to convert Log file to CSV using bash

Is it possible to turn this log entry into a properly formatted csv file using sed/awk? I've tried multiple ways to do this using sed/awk. Alas I couldn't do it. Before I do it in perl. is this ...
0
votes
1answer
14 views

Bash script: array elements containing space character

I'm getting started with bash scripting. I'm working with array elements that contain space characters. In the code below, the third array element is "Accessory Engine". I tried to set the space ...
2
votes
3answers
58 views

How to get tab completion when using curly braces in Bash

I want to have tab completion when using curly braces in a command in bash. For example: cp ~/html/{foo bar.txt whatever} /var/www/html/ I want the tab completion for the files stated in the curly ...
11
votes
3answers
2k views

Can't indent heredoc to match nesting's indent

If there's a "First World Problems" for scripting, this would be it. I have the following code in a script I'm updating: if [ $diffLines -eq 1 ]; then dateLastChanged=$(stat --format '%y' ...
10
votes
4answers
5k views

How to insert a new line after every second line?

sed/bash/wharever :D INPUT: sadf asdf yxcv cxv eqrt asdf OUTPUT: sadf asdf yxcv cxv eqrt asdf
26
votes
7answers
6k views

What Unix commands can be used as a semaphore/lock?

I want to run multiple Bash shell scripts in parallel. However, I want to avoid race conditions. What Unix commands are truly atomic that I could use for this purpose, and how can I use them?
11
votes
5answers
1k views

Shell: “Display all 2588 possibilities?”

So, I was moving my laptop around (and I have the bad habit of setting things on the keyboard...) and I woke up to discover this: $ Display all 2588 possibilities? (y or n) What command would ...
2
votes
1answer
237 views

Mystifying command not found at login

I've just set up Arch Linux (not my first time). Everything installed correctly but when I login (X isn't installed yet) I see: Arch Linux 3.8.4-1-ARCH (tty1) mgoszcz2 login: root Password: Last ...
0
votes
2answers
21 views

redirect output from interface?

I am echoing an AT command to a modem interface (/dev/ttyUSB3) and the command runs successfully. For instance the below command works and has an output of OK: echo -e "ATZ\r" > /dev/ttyUSB3 I ...
1
vote
1answer
649 views

bash: /etc/bash.bashrc: Permission denied whenever I open a terminal

On Ubuntu 13.10, when I open a new terminal, I sometimes get the following output on the terminal: bash: /etc/bash.bashrc: Permission denied However, the permissions should be fine: >ls -l ...
0
votes
2answers
44 views

Untar and gzip from multiple sub directories

I have a directory which consists of multiple sub-directories. Each subdirectory has a tar.gz file which on untar gives two files namely R1.fastq and R2.fastq. I want to untar the tar file and ...
3
votes
3answers
4k views

Pipe assigns variable

For simplicity I would like to do echo cart | assign spo; echo $spo Output: cart Does such an appliance exist such as assign? I am aware of all the ways to do this using substitution.
2
votes
3answers
68 views

Using find with 2 sets of variables

I want to be able to run a find command in my bash script that will find files based on two seperate variables. I've gotten this far but I'm not sure how to get the final result workingfind . -user ...
1
vote
1answer
38 views

Read a character from an x-y coordinate on the screen

Is there a way in bash to read a character from an x-y coordinate on the screen? This command would be something similar to cget 12 30 which would return the character at the 12th row and 30th ...
0
votes
1answer
27 views

Opening a socket in Kali Linux using bash scripts

I know how to open a TCP or UDP socket in Ubuntu, with the following command : exec 3<>/dev/tcp/google.com/80 for example: we can open a TCP socket on port 80, but in Kali Linux there's no ...
1
vote
2answers
34 views

Do programs source .bashrc when run?

I append to my PATH environment variable in my .bashrc file (Ubuntu v12). I also have a service (Atlassian Bamboo) that relies on the modifications to PATH. When I restart the service (which runs as ...
2
votes
2answers
53 views

Using the output of `grep` as variable in second command

I currently have 2 bash command line strings I use to gather data needed for a certain task. I was trying to simplify and have only one command used to gather the data without using a script. First I ...
0
votes
2answers
18 views

The best way to add Unix Shell variables to CURL GET request

Let’s say I use curl –X GET command with the following link: “$WEBSITE_URL/ACTION_NAME/ACTION1;id=$ID?Command=TEST&id1=$ID1&id2=$ID2&id3=$ID3” As you can see, there are some $variables ...
1
vote
2answers
46 views

BASH: Command not running, special character '�' suddenly appeared (Ubuntu)

When I erroneously type 'ñ' (expecting to type any command) and then remove it and type the correct letter, the output returns the command with a special character attached �, obviously the shell ...
0
votes
1answer
12 views

Universal .bashrc alias showing results of sysytemctl start command

This is small .bashrc alias that allows me to see results of starting service alias systemctl start apache='systemctl start apache && echo SUCCESS || echo failure' How can i modify to work ...
0
votes
1answer
25 views

I don't see .bashrc file in my /home and /etc/skel direcories

I am running linux mint 17.1 rebecca, but I have found it quite different with other distros I am used to, in /home and /etc/skel there's no .bashrc I don't know if i mess up with something or it is ...
0
votes
1answer
18 views

Tar Create and Split files into subdir

I have this command: tar -cf - input/* | split --bytes=1m Which splits my huge gz files into small ones. This works fine. However I want the output (the small files) to be created in the input/ ...
11
votes
3answers
578 views

Terminal vs bash? [duplicate]

I'm on a Mac but I think this is generally Unix-applicable. I'm in the process of learning shell scripting and there's something I seem to be missing. When I'm in the ordinary terminal, I can use ...
19
votes
6answers
1k views

Do we have more history for cd?

cd - can move to the last visited directory. Can we visit more history other than the last one?
8
votes
2answers
404 views

Run another command before running the command the user wants to run

Let's say I want to modify the original behavior of the ls tool this way: $ ls Hello World file1 file2 ... How can I do this? When running ls I would like to run another command let's say echo ...
3
votes
2answers
108 views

Assign specific line from a variable to another variable

I would like to take a specific line from a variable to another variable. I tried this but it doesn't work: c="1.apple 2.banna 3.peach" read "Please choose fruit [1-3]:" t a=$c | awk "NR==$t" echo ...
2
votes
1answer
15 views

Is there an alternative to using rbash to restrict a user on my system?

Basically at the moment I am using rbash to stop a user from leaving his directory on my system. The problem with this is, there is a script in my bin which he needs to be able to run from a script in ...
1
vote
3answers
205 views

How to copy files from the folder without the folder itself

I'm trying to copy files and subfolders from A folder without the A itself. For instance, A folder contains next: | file1.txt | file2.txt | subfolder1 Executing next command gives me ...
1
vote
2answers
48 views

ls .. doesn't work properly with symlinks

I have directories set up a bit like this ~/code ~/code/src ~/code/build -> /path/to/somewhere/else That last one's a symlink. If I do this cd ~/code/build ls .. then I get the listing for ...
60
votes
18answers
46k views

How can I get my external IP address in bash?

I need to find my external IP address from a bash script. At the moment I use this function: myip () { lwp-request -o text checkip.dyndns.org | awk '{ print $NF }' } But it depends on ...
1
vote
1answer
49 views

bash - command not found [on hold]

I have a script [pic@pic Desktop]$ cat skrypt.sh #!/bin/bash awk '{sub(/#echo "Wstałem"/,"#echo \"Wstałem\""); print $0 > "skrypt.sh"}' skrypt.sh awk '{sub(/awk/,"#awk"); print $0 > ...
1
vote
3answers
28 views

Loop to check whether a Debian package is installed or not

I like to check whether several packages are installed or not on Debian/Ubuntu Here is my attempt at a script to do this: query=`dpkg-query -W -f '${Status}'` ok="install ok" if ! [ `$query` curl ...
3
votes
3answers
149 views

Piping a script with “read” to bash

I need to run a script by piping it through bash with wget(rather than running it directly with bash). $ wget -O - http://example.com/my-script.sh | bash It's not working because my script has read ...
2
votes
3answers
980 views

Query list of servers for memory/cpu allocated

Running RHEL 6.2, trying to write a bash script to SSH to a list of remote servers, and write the CPUs and Total Memory to a file, one line per host in the following format: HOSTNAME1 CPUS: 12 ...
1
vote
1answer
51 views

Example for adding

Example 1. Adding to the console works well pic@pic:~/Desktop$ a="$(date +%s)" pic@pic:~/Desktop$ b="$(date +%s)" pic@pic:~/Desktop$ echo $[a+b] 2844184057 pic@pic:~/Desktop$ Example 2. It's the ...
1
vote
1answer
28 views

Sourcing a redistributable script by default

I am creating a bash script which I wish to release on github. The script needs to access the command history but this is not possible without sourcing that script. I don't want users to put it in ...
15
votes
3answers
2k views

Can I configure bash to execute “clear” before every command typed in the console?

I would like to configure bash to execute clear command every time I type some command in the terminal (before executing my command). How can I do that? I'm using Debian Linux.
1
vote
2answers
48 views

Read line from file then delete

How can I read a series of lines from a file and then remove each line? Obviously I can read like this: while read -r line; do echo $line done < myfile.txt But if I do this: while read -r ...