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.
26,128
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How to modify this git alias so it can be run without the need to put multiword commands in quotation?
I have this alias:
git config --global alias.all '!f() { ls -R -d */.git | xargs -I{} bash -c "echo {} && git -C {}/../ $1"; }; f'
It currently works fine when I run it like :
git ...
- 123
0
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2
answers
56
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Regarding Nested loops
I had 3 array array1, array2, array3 where array 3 is the value of first two array. for example: FO=2.0, FF=3.5, FC=4.5 and so on. I want to give k (third loop) values of array3, like while running FO ...
- 1
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14
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macos/bash: read "hangs" when executing script second time as another user with stdout redirected before
Hello! My second file descriptors question.
Context: Still new at this, I certainly don't get file descriptors. Magic. Unpredictable magic at that, that sometimes works. (joke, but you probably get my ...
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0
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17
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Looping ssh command with `while` stopped at first iteration but not `for` [duplicate]
The following didn't work:
cat /etc/hosts | grep -vE '(^(#|$)|127.0.0.1|ff|::|node)' | awk '{print $1}' | while read -r host; do
echo "Looking at $host"
ssh "$host" ...
- 2,075
1
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0
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18
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While Loop Exits After Calling Function [duplicate]
I'm trying to do a db backup script using Bash.
When adding a "Resume" feature to the script, I do the following loop calling defined functions to do step by step (depending on the .lock ...
- 111
0
votes
1
answer
38
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basename complains about missing operand using unshare
If I try to create namespaces, basename complains about missing operand:
sudo unshare --mount --ipc --uts --pid --fork --user /bin/bash
basename: missing operand
Try 'basename --help' for more ...
- 4,469
-2
votes
1
answer
59
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How to convert multiple columns to rows in shell (unpivoting)
I have a tab separated table with hundreds of columns and rows, like that:
OTUId AC0184 AC0250 AC0257 AC0258 AC0262 AC0263 AC0289 AC0293
OTU549024624 51659 0 0 0 0 0 0 0
OTU565712448 108 0 0 0 0 0 0 0 ...
-1
votes
1
answer
55
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Why doesn't 'export' give the export attribute while 'set -a' does?
From man bash (GNU bash, version 5.2.21(1)-release (x86_64-pc-cygwin)):
set [-abefhkmnptuvxBCEHPT] [-o option-name] [--] [-] [arg ...]
-a Each variable or function that is created or modified is ...
- 619
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1
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44
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How can I get stderr from mbuffer written to log file when using tee?
Having a bash script that essential only doing:
mbuffer --md5 -i dummy.tar -o /dev/null
A user of this script wants to use tee and store the output messages in a log file.
./script.sh 2>&1 | ...
- 3
2
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4
answers
330
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output of a command framed by a couple of '#' characters
I want to be greeted by
# #####################################################
# ### PostgreSQL 16.3 #################################
# #####################################################
on ...
- 161
0
votes
1
answer
36
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tar returning different exit code when wrapped inside if statement [duplicate]
I have a script which creates a tar archive filtered through xz. I have wrapped the tar command inside an if statement so the script can take different actions depending on whether the archive was ...
1
vote
2
answers
74
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How to append multi-line text with spaces to end of file if that text does not exist in bash?
I'm trying to append a text string that contains newlines and spaces to a file if the whole string doesn't already exist in that file.
Ideally done in a way that's portable across MacOS and Linux
I ...
- 626
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0
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17
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How do I determine if a path is a fifo? [duplicate]
I have some bash shell code that runs
if [[ ! -s "$1" ]]
to determine if $1 is a non-empty file
This test fails if $1 is a fifo, even though the fifo has data in it ready to be read.
Is ...
- 207
-1
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3
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90
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Delete 2-line paragraphs, keep 3-line paragraphs, maintain newline between all
On a Linux machine with GNU tools I have an ascii file that consists of only 2-line and 3-line paragraphs, each paragraph separated by a newline. All 2-line paragraphs are to be deleted so that all 3-...
3
votes
1
answer
40
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Is it normal for "complete -p git" to error until I autocomplete git first?
If I restart my terminal, I get an error when I type this:
$ complete -p git
bash: complete: git: no completion specification
But if I type git tab then run the complete command again, I get a ...
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