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.
26,711
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How can UserA programmatically replace a text string within a file they own that's located in /etc?
A non-root linux user owns a text file that's located in /etc, where the non-root linux user does not have permission to create files. The non-root linux user can edit the file manually via vi without ...
- 153
1
vote
1
answer
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What is PS1 prompt \[\e]0; vs \[\e]2; , it looks like one is for title name of tab, one is for title name of windows
here is my ps1
does someone know documents about this?
export PS1='\[\e]0;YYY@\h:\w\a\]\[\e]2;XXX\W\a\e[32;40m\]\[\e[36;40m\]$?\[\e[31;40m\]\D{%d}\[\e[35;40m\]\D{%H%M}\[\e[36;40m\]\W\[\e[32;40m\]>\[...
- 31
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1
answer
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How to split a number into unequal parts in Bash
Hypothetic example: There is a number that I will split into x parts (smaller numbers, in a range you see in the example).
I need a way, ideally a one liner for the Linux Bash, to split a large number ...
- 59
-2
votes
1
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How do I get lastlog timestamps in a generic format?
I have multiple Ubuntu machines in different locations. I want to collect the last login information from these machines. However, when I use the lastlog command, it returns dates in different formats....
0
votes
1
answer
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gpg suddenly won't ask for password, "cancelled by user"
Suddenly, gpg won't ask for password when trying to decrypt file and instead says "cancelled by user". I have already tried..
GPG_TTY=$(tty)
export GPG_TTY
with no effect. I get the ...
- 11
1
vote
1
answer
26
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`pushd` inside a while loop from file contents does not behave the same depending on read method [duplicate]
I'm pushing directories to my stack using a while loop that reads the contents of a file. I've tried two approaches that should be equivalent, but they behave different.
Approach 1
export ...
3
votes
2
answers
282
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How do quotes work in bash regex regarding reserved characters?
Is there any special bash reserved characters in bash regex expression?
ex:
eg: if [[ $url =~ ^https:\/\/www\.youtube\.com\/playlist\?(.+&)?list= ]]; then echo "URL matches the regex"; ...
- 133
13
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3
answers
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Why does setting a variable readonly in the outer scope prevent defining a local variable with the same name?
I've found nothing about this in all my searching.
In the code below, Bar1 acts like I'd expect a "regular" variable to act (since help declare says that -g is only "seen" in ...
- 1,134
0
votes
1
answer
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How to add categories in `free` command
I can extract the amount of memory used by running the following two commands from terminal:
free -h | awk '/^Mem:/ {print $3}' This shows the used memory, e.g. 4.8Gi.
free -h | awk '/^Mem:/ {print $5}...
- 37
-1
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1
answer
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Bash deploy script only works the first time?
This script works perfectly the first time after starting it but when it's done it only continues to output zip_count: 0 afterwards. There seems to be some strange cache?
I run the script inside Git ...
- 99
2
votes
1
answer
48
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Is there a way to `exec` a pipeline or exit shell after launching a pipeline?
I'm writing a shell wrapper script that is supposed to act as a pager (receiving input on stdin and performing output on a tty).
This wrapper prepares environment and command lines, then launches two ...
- 5,467
-2
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0
answers
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Searching for a bootable USB Linux image to run a single bash script without user interaction
I'm looking for a lightweight Linux distribution that can be booted from a USB device with the sole purpose of executing a single bash script and then shutting down automatically. My requirements are:
...
- 1
2
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2
answers
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set -o xtrace for just one line? [duplicate]
bash 4.4.20(1) on RHEL 8.4.
set -x ; ./blarge ; set +x works, of course, but it's just that much more stuff to remember to remove when you're finished. And gets sticky if you're running ssh, sudo, ...
- 1,134
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votes
4
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Getting output of /usr/bin/time in CSV format
I am using gawk to parse the output of macos' /usr/bin/time into CSV format as shown below. The problem is that gawk is returning the 'involuntary context switches' value for 'voluntary context ...
- 13
1
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1
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Shell script to run command and show output in notification box
I have command line utility that generates text strings, by running a command within the directory:
./Utility -P
it prints output on terminal. How to make a shell script showing the generated string ...
- 533