Questions tagged [bash]
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. For shell scripts with errors/syntax errors, please check them with the shellcheck program (or in the web shellcheck server at https://shellcheck.net) before posting here.
25,631
questions
0
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0
answers
20
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Stopping parameter expansion in write_file content of cloud-init userdata
Background
I'm using Terraform and cloud-init to provision an Ubuntu VM.
The Terraform template contains an embedded cloud-init user_data section that contains a write_file directive to write a bash ...
0
votes
2
answers
63
views
What mean $ in $PS1 envoriment variable?
For example, if I check $PS1 variable I get it:
[root@ENGDADOS ~]# echo $PS1
[\u@\h \W]\$
But if I reenter this exact variable, it changes from # (root) to $ (usually normal user)
[root@ENGDADOS ~]# ...
- 383
0
votes
1
answer
30
views
handling columns with whitespaces
A hashing command gives the hash and the path separated by a whitespace:
k3j48fajsdjf4w8fj path to file/file 1.txt
I want to create a table where one column is the hash and the other column is the ...
- 153
0
votes
4
answers
80
views
how to print first word from a string with multiple words without space?
I have a shell script to print appimage filenames inside a folder like this
#! /bin/bash
Dir="$HOME/Applications/"
Dir2="$HOME/Downloads/"
cd -P "$Dir"
for f in *....
-3
votes
1
answer
49
views
substitute string within a range [duplicate]
Suppose I have text file such as
A1
A2
A3
A4
A7
A27
A31
A56
A100
A8
A11
and I want output like this where A1 to A30 shoud be sustituted with A1 and A31 to A100 should be substituted with A2, using ...
- 17
0
votes
2
answers
33
views
How to list only first directories in zip file?
unzip -l show all directory and sub-directories/files.
I'd like to list only the first directory structure insize a zip file, something like -maxdepth 1 of find command.
Is there some way to do it ...
- 383
0
votes
3
answers
78
views
Sorting number ranges from two arrays in bash
I have two arrays with the same number of elements I want to manipulate. They are read from a file into two arrays (odd numbered lines go into array one, even numbered into array 2):
arr1=("1&...
- 1
0
votes
2
answers
39
views
> symbol appearing when interactively defining function in bash
The behaviour of my shell environment changed:
Earlier, when pasting a function definition e.g.
function exampleFunc {
echo hello
}
to the shell, it would display as formatted and register the ...
- 383
0
votes
0
answers
29
views
Script for awscli check not working with crontab schedule
I have written a small code snippet to check the aws cli version
#!/usr/bin/env bash
if [ -e "/usr/local/bin/aws" ];
then
myAWS="/usr/local/bin/aws"
else
...
- 1
-3
votes
1
answer
79
views
How to write a shell script to create the network configuration file
How can I create the below configuration file using shell script? The file should be created automatically using the script, using input from the user.
The path where the file is to be created is /etc/...
- 1
-1
votes
1
answer
29
views
What is the difference betweem ` and ' in bash? [duplicate]
Today I noticed if I run:
ldd `which bash`
I get the expected output.
But when I run
ldd 'which bash'
I get error ./which bash: No such file or directory.
So what is the difference between the two ...
- 191
0
votes
0
answers
43
views
Bash script won't work if it's run from gnome files
I have the following script
#!/bin/bash
nohup /home/user/Android/Sdk/emulator/emulator @Pixel_4_API_30 &
The script has 755 access and if I try to run it from the Gnome Files option "Run as ...
1
vote
1
answer
28
views
Concatenating string passed into a control sequence
I have this echo invocation that prints a blue bar in a Bash terminal:
echo $'\e[48;2;0;0;255m \e[0m'
I would like to pass some variables to it, something like (this doesn't work):
...
- 11
1
vote
1
answer
89
views
bash if-else statement not working as expected
I have a script in which I check the execution codes (0 assign to SUCCESS and 1 assign to FAILURE). I am using a if-else statement to check whether the execution code is 0 or 1.
If it is 0 I want to ...
- 13
2
votes
1
answer
37
views
How to read hourly files of a day and merge it?
I have a folder of Netcdf files. These files are six hourly wind files for a month. I want to combine all the files. I don't know how to make a shell script to read the files in order of hour to ...
0
votes
1
answer
31
views
Bash variable with :
I am new to bash and am trying to understand a script I have been passed.
Within the script, I have the following variable:
site_source="${site_host[$i]}:public_html"
Can anyone confirm ...
- 271
1
vote
1
answer
54
views
Why are bash and git-bash results different?
Newbie trying to learn bash and jq. I'm on a Windows machine so I thought I'd test with git bash - I thought git bash was identical to bash running on Linux.
For my test, I'm trying to extract a list ...
- 119
0
votes
0
answers
21
views
find (fd) execute with custom function and multiple parameters
I'm quite new to bash scripting so excuse the rough script. I'm writing a simple script that goes through all directories that has a .git directory in them, and checks if the worktree is clean or ...
- 101
-1
votes
1
answer
58
views
Remove duplicate lines without sorting and ignore case
So, let's say I want to remove duplicate lines without sorting, as in this thread, but I also want to remove duplicate lines that aren't case sensitive without converting all the strings to uppercase ...
0
votes
1
answer
48
views
Why isn't my systemd timer executing my sh script?
My youtube.sh file located in /home/deck/Desktop/youtube.sh:
#1/bin/env bash
pactl -- set-sink-volume 0 100%
xdg-open A youtube video link
My youtube.timer file located in /etc/systemd/system/youtube....
0
votes
2
answers
68
views
Is it bad practice to use sed to pass a variable through to another script?
There are two shell scripts.
One of which is a source file source.sh. This source file will exist for multiple people each with their own directories.
name = "foo"
The main script main.sh ...
- 3
0
votes
0
answers
15
views
Execute when dark mode is toogled
I want to create a simple bash file and I want it to run whenever I turn on or off the darkmode.
Where and how should I place the file??
- 140
0
votes
0
answers
27
views
Configuring a service unit to launch a bash script. Why is this failing?
I am asking systemd to supervise and control a process but for some reason, it is failing.
Check the output at the end of the question
I have a bash script in /usr/sbin/ros_diagnostics.sh that ...
- 2,250
11
votes
1
answer
881
views
Use the 'cp' command in a Bash script and exclude a specific directory
I need to run this command in a shell script to copy source > destination and exclude a folder.
No rsync, tar, find, mv, etc.
Exactly this command:
cp -var test/!(test2) testbkp
In the shell it ...
- 2,323
0
votes
0
answers
95
views
direnv and environment variables
I'm trying to get autoactivation of conda/mamba environments working using direnv but I'm running across a problem that seems to be due to my lack of understanding of how bash scripts work with ...
- 1
0
votes
1
answer
48
views
Decanting code in $HOME/.bashrc into a function
I have the following code fragment in my $HOME/.bashrc file:
export RED='\e[0;31m'
export GREEN='\e[0;32m'
export YELLOW='\e[0;33m'
export BLUE='\e[0;34m'
export MAGENTA='\e[0;35m'
export CYAN='\e[0;...
- 483
0
votes
1
answer
40
views
Bash create parameter named array within function
I'm attempting to write a function that writes arrays with a name that's passed in. Given the following bash function:
function writeToArray {
local name="$1"
echo "$name"
...
- 383
1
vote
0
answers
33
views
Reusing password to unlock KeePassXC database and ask user for new password when adding new KeePassXC entry password
I do have an issue passing on password to keepassxc-cli in bash. I would like it to unlock and ask for adding a password on KeePassXC entry.
When I ask user for a password e.g. read for KeePassXC DB ...
- 4,753
1
vote
1
answer
35
views
Why this systemctl isn't starting?
It's on Debian 11. The file PwOn.service:
[Unit]
Description=Send a message with a telegram bot
After=network.target
Wants=network-online.target
[Service]
Type=simple
ExecStart=/usr/bin/...
- 11
0
votes
2
answers
44
views
Command substitution not working with environment variable
I have this command which I want to variabilize. Particularly I want the latest argument presence to depend on an environment variable.
ansible-playbook --inventory inventories/ssg-dev deploy.yml --...
- 103
0
votes
0
answers
17
views
Mail remote commands output on failure
I would like to run a command on a remote server and send an email alert (locally) in case of failure. As surprising it is this actually works:
ssh -p1222 root@10.4.4.4 'cd /root/chk; md5sum -c /root/...
- 1
0
votes
0
answers
25
views
bash script to change avatar in Telegram
Can I change avatar picture in Telegram Desktop via bash script?
I searched the Telegram folder by the name of the picture file I set previously as avatar but didn't find anything:
grep "...
- 1,235
0
votes
1
answer
39
views
how to close stdout for program from shell?
I mean not to redirect stdout to /dev/null, but block stdout before starting my program, so for example all of my write(1, "dd", 2); will return -1 as if stdout doesn't exists in my device.
0
votes
1
answer
63
views
How to run bash scripts in sequence and in infinite loop?
How do I run
/tmp/1.sh
/tmp/2.sh
/tmp/3.sh
/tmp/4.sh
and then loop back to run /tmp/1.sh again? preferably in an infinite loop
- 23
-1
votes
0
answers
63
views
What is the most POSIX-compliant shell?
Just out of curiosity, I've been on a long unsuccessful quest to finding the absolutely most POSIX compliant shell out there. From what I now know, mrsh is the top candidate. Although yash might also ...
1
vote
2
answers
61
views
Hacking LD_LIBRARY_PATH to use a recent bash from a chroot
I try to get a more up to date version of bash from LinuxMint.
I have a chroot with Debian Sid in my box.
What I try to do in a bash wrapper script, early in my PATH
#!/bin/bash
LD_LIBRARY_PATH=/path/...
0
votes
2
answers
60
views
Unix. Run script across multiple dirs on specific files, where pathname has regex
I want to make a bash script (split.sh) that iterates across multiple dirs with same suffix, and then runs a function for specific files within them. I am almost there:
#!/bin/bash
path="/mypath/...
- 99
1
vote
1
answer
34
views
Separate variable scope spawning commands under job control
Is is possible in bash - or other sh-derivative shell - to run in the foreground from command-line a list of commands that have their own variable scope (so any values assigned to variables in that ...
0
votes
1
answer
83
views
evaluate a string that is a bash if-statement
My script has a function do_command() that prints a command and then executes it. I want to put my commands in a bash array of strings, and then print _ execute them with this function. But when I try ...
- 539
-3
votes
2
answers
102
views
Bash script to calculate within a CSV [closed]
This is my CSV File:
Number;Reference;EANNumber;Manufacturer;Price_B2B;Price_B2B_Dis;Price_B2B_DisPer;Price_B2B_DisAmount;Price_B2C_exVAT;Price_B2C_inVAT
2330113;BP3141;1,31304E+11;APC;13;13;0;0;0;0;;;...
- 3
2
votes
1
answer
84
views
Simple template engine for bash, that can use csv data?
I'd often like to quickly take some data, and apply it to a template in bash.
e.g. imagine doing the following
$ seq 1 2 | eztemplate 'this is a {1} test'
this is a 1 test
this is a 2 test
$ ...
- 1,579
0
votes
1
answer
26
views
Why does the test command apparently choke on a for loop variable?
I want to determine all broken symlinks within a directory.
In ignorance of a better solution, I tried this simple bash one-liner (bash version is 4.2.46, which may be worth mentioning because it's a ...
- 193
0
votes
2
answers
26
views
List files where searched term occurs more than a Threshold
I have a command like
rga --files-with-matches --count-matches --sort path -i -e "use cases?" -e "user stor(y|ies)" -e "Technical debt" -e "Code Quality" -e &...
- 1,996
0
votes
1
answer
37
views
bash: running a sequence of commands in a subshell with fail-on-error
I have a sequence of commands I want to run in such a way that when any command fails, the rest of the commands should no longer be executed. Let's assume the sequence of commands is
echo foo
false
...
- 391
0
votes
2
answers
33
views
Can not move searched files to a directory
The output of the following command is:
$ rga --heading -l --context 3 --sort path -i -e "use cases?" -e "user stor(y|ies)" -e "Technical debt"
Stepanek G. - Software ...
- 1,996
0
votes
0
answers
54
views
sshpass No such file or directory
need add string to file on remote ssh server without prompting sudo password
myuser=testuser
$ sshpass -p "$mypass" ssh -t -o StrictHostKeycheking=no $myuser@$myhost "echo $mypass | ...
- 83
0
votes
0
answers
21
views
How can I make e2fsck non interactive?
When I run "e2fsck" command through cli it asks for options like asking for abort, force rewrite etc, and the process get completed successfully. But I want to run "e2fsck" command ...
0
votes
0
answers
13
views
How can I can autocomplete for my custom command, based on the name of files in another directory?
This is my requirement. We have a custom Ssh command that uses ssh under the hood, but automatically provides some options based on some conditions.
For example, our developers can write Ssh example....
- 499
0
votes
2
answers
38
views
Special array from list of items in current dir
I want to extract a specially formatted array from the list of current dir.
$ ls
Output:
fileABC.ext1
filePQR.ext2
dirMNO
dirFGH
I want only the dir and files of specific extension
I want an array ...
- 140
0
votes
0
answers
46
views
Is there a bash mode that automatically quotes parameter expansion?
I have a script called render.sh that looks like this:
#!/usr/bin/env bash
if [[ -f "${ENVIRONMENT}.yaml" ]]; then
ENV_YAML="-f ${ENVIRONMENT}.yaml"
fi
set -x
helm3 template &...
- 101