Questions specific to GNU’s Bourne Again SHell, as opposed to other Bourne/POSIX shells. For questions about Unix shells in general, use the /shell tag instead.

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3
votes
3answers
272 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
2answers
45 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 ...
1
vote
1answer
3k views

Bash script: array elements containing space character [duplicate]

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 ...
1
vote
1answer
242 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 ...
4
votes
1answer
3k 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
3answers
3k 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 ...
2
votes
3answers
285 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 ...
2
votes
3answers
158 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 $...
0
votes
2answers
166 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 ...
0
votes
1answer
626 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
1answer
213 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
2answers
136 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 ...
0
votes
3answers
4k 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
3answers
10k 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
131 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/ ...
1
vote
1answer
97 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 ...
1
vote
2answers
275 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
4k 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 ...
3
votes
1answer
139 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
2answers
107 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 /...
5
votes
3answers
7k 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 ...
9
votes
2answers
521 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 "...
15
votes
3answers
13k 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 ...
1
vote
1answer
365 views

bash - command not found [closed]

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 > "skrypt....
1
vote
3answers
465 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 ==...
1
vote
1answer
62 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 ...
0
votes
1answer
41 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 ...
2
votes
1answer
128 views

How to execute 'clear' bash command before any other command is executed?

I see the question at Can I configure bash to execute "clear" before every command typed in the console?, but the answers there are not valid for GNU bash, version 3.2.53(1)-release (x86_64-...
3
votes
3answers
564 views

BASH: �ls: command not found when typing 'ñ' by mistake

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 don'...
4
votes
2answers
361 views

Appending works without >> when redirecting standard output and error

I have a file test.txt and have no file named test. When I tried ls test test.txt > new 2>new I was expecting new to be overwritten since >> is not used. But in the output file I got ...
0
votes
0answers
15 views

Escape ampersand in bash variable used as a sed argument [duplicate]

I have a template Hello NAME welcome and want to replace NAME with data like "Judy&Mary". Why does this not work? TEMPLATE="Hello NAME welcome" DATA="Judy&Mary" echo $TEMPLATE | sed -e "s/...
1
vote
3answers
3k 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 ...
-1
votes
1answer
201 views

Check exist file on another pc

Yesterday I had ask how to use my tftp protocol in my bash script: Debian - Using TFTP in a bash script And now I have a problem with my tftp protocol. The file who was taken depend of my Hostname. ...
1
vote
2answers
670 views

Turn off mail notification in terminal

I'm running some cron jobs on my machine and every time I fire up a terminal session I'm getting a 'You have mail' message (the job produces output on success which gets mailed to me). Any way to ...
3
votes
2answers
181 views

Command to output to current prompt

Is there any command that will output text to the (next) command prompt? I would like to write a function, which upon execution, will perform some commands and then "suggest" the next command to be ...
1
vote
1answer
141 views

How can I use regex to extract the text following two conditions into a variable?

I'd like to extract a setting for a given host in the ssh_config file and put it into a variable. Host mysite HostName 123.1.1.1 User myuser Port 13245 GSSAPIAuthentication no ...
0
votes
4answers
2k views

How do i change the case (upper and lower case) of strings in my variable?

"Enter test: " read test if [[ $test == "a" ]]; then echo "worked" else echo "failed" fi It's a simple illustration of test i'm doing, but if i enter "A", it will fail, is there anything i ...
1
vote
0answers
51 views

How to make sure to get the Main/External IP without regard to network device type/name

Hello, I need to make sure I have the external or at least the main IP address for a given machine, regardless to the device type/name. I quickly wrote that tiny script for that purpose, but I need to ...
2
votes
1answer
6k views

Correct syntax to avoid bash 'ambiguous redirect' message

I am trying to execute a command which accumulates stdout into an existing file and sends the error messages to another using the command below. commmand >> /home/user/accumulate_output.log 2&...
0
votes
1answer
2k views

Debian - Using TFTP in a bash script

I'm actually using RPiTC (Raspberry Pi Thin Client). I had create a script to see if my Hostname has the same name than a file. And now I want to say "If my Hostname don't have the same name than my ...
0
votes
4answers
167 views

bash script, list all the files over a specific size

so I have a line of code like this: result=`find . -type f -size -1000c -print0 | xargs -0 ls -Sh | head` for i in $result; do item=`wc -c $i` echo $item1 done this will print out all the ...
5
votes
3answers
2k 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
1answer
2k views

Bash script, ask for user input, to change a directory, sub directorys, and file's mtime atime linux recursively

Using GNU bash, version 4.3.11(1)-release (x86_64-pc-linux-gnu) I am a bash scripting novice, not sure where to begin except at shebang #!. The following command. touch -a -m -t 201501010000.00 ...
3
votes
4answers
288 views

fgrep beginning of line?

I'd like to use fgrep to handle searching literal words with periods and other meta-characters in grep, but I need to ensure the word is at the beginning of the line. For example, fgrep 'miss.' will ...
2
votes
2answers
106 views

“dpkg -l” receives shell wildcard character?

In a bash shell where I have globbing enabled if I execute ls -l *ou*, then shell should pass out.dot and out.png as arguments to ls, i.e. ls never sees the * character. However, looks like in case of ...
0
votes
2answers
397 views

Delete last character of last item in a bash array

I have such array: Array={123},{456} Now I want to delete the last item 6.
1
vote
1answer
330 views

Connecting 3 OpenVPN connections through a shell script

For work I need to connect to 3 different OpenVPN connections every day. I'm using a shell script to speed this up, but I feel like it could be done better. Currently my script is: #!/bin/bash cd ~/...
0
votes
2answers
100 views

Bash variable substitution problem

I have a problem with variable substitution in bash. I'm doing like as explained in below code, but cd $d is not going into original directory i.e. after expanding $var export var="/a/b/c" for d \`...
2
votes
1answer
2k views

Run a command under sudo over SSH

I am accessing remote machine in Linux using Bash scripting.My code is as follows #!/bin/bash ssh -i manu_bp.pem ubuntu@54.68.67.68 <<EOF sudo -s cat /opt/revsw-config/apache/...
3
votes
2answers
807 views

How can I invoke a prompt for an ssh key passphrase during the execution of a script?

In my ssh_config file there are multiple entries for sites on the same server such as: Host site1 HostName 123.1.1.1 User myuser Port 13245 GSSAPIAuthentication no ...