All Questions
Tagged with bash-functions or bash
27,269 questions
0
votes
2
answers
71
views
POSIX sh alternative to Bash's [[ ]]
I am using this code to parse the first argument passed to my script. It error handles and it works just the way I want it:
if [ -z "$action" ]; then
printf "[${c_RED}ERROR${c_RESET}...
2
votes
3
answers
161
views
bash syntax: what does '[@]+' mean? [duplicate]
I have a script that parses command line arguments.
The intro to the loop to iterate over the argument array looks like this:
for arg in ${args[@]+"${args[@]}"}; do
Can someone explain this ...
0
votes
0
answers
51
views
how to convert hex memory dump to Docsis config file?
Hex memory dump is Docsis config file. Is it possible to convert this hex dump info valid Docsis config file? Preferably, using Perl and DOCSIS::ConfigFile module. (or Python scripts, python-docsis). ...
- 1,473
4
votes
1
answer
180
views
Choice of field separator affects sort's ordering
Suppose we have a script named test_sort in our $PATH with the following contents:
#!/bin/bash
function echo_text () {
printf -- "%s\n" "$fc$oc$fs$lc"
printf -- "%s\n&...
- 4,478
0
votes
2
answers
137
views
Process sed capture group with a bash function before replacement: "sh: 1: <bash function>: not found"
So, I was playing around with this answer, when I found that neither
printf_stdin () {
read input
printf "$input"
}
sed "/lorem ipsum foobar/ {
s/'/'\"'\"'/g
s/\...
- 145
2
votes
1
answer
36
views
Shell bracket list wildcard doesn't work with variable [duplicate]
The following works:
ls {000/487,000/488,000/489,000/490,000/491,000/492}
...many files being listed
But this doesn't. Why ?
LIST=000/487,000/488,000/489,000/490,000/491,000/492
ls {$LIST}
ls: cannot ...
- 659
1
vote
0
answers
53
views
Running XFCE on Debian Trixie. Bash history is not saving any sudo commands
Bash history works OK for except for sudo commands.
Code from .bashrc follows.
How can I modify the behaviour to include anything starting with sudo?
NOTE. This behaviour is the same with a brand new ...
- 11
2
votes
1
answer
97
views
Bash: function in a script with flags
Using https://stackoverflow.com/a/7948533/31298396, we can implement flags for a script testing as follows:
#!/bin/bash
# Flags
# Source: https://stackoverflow.com/a/7948533/31298396
TEMP=$(getopt ...
- 145
0
votes
1
answer
64
views
Bash Script Linux - combines a QUIET function with other functions without hiding some of them
#!/bin/bash
DefaultColor="\033[0m"
GREEN="\033[32m"
RED="\033[31m"
PURPLE="\033[35m"
YELLOW="\033[33m"
CYAN="\033[36m"
CmdOk="\033[...
- 3
5
votes
1
answer
375
views
locking scripts using flock - can same file descriptor be used concurrently?
Common method for preventing concurrent runs for a given script is utilizing flock as:
LOCK=/var/lock/my-lock
exec 9>>"$LOCK"
if ! flock --exclusive --nonblock 9; then
echo "...
- 71
6
votes
2
answers
331
views
suppress stderr when inputting a file to a variable
var="$(cat no-exists)"
var="$(< no-exists)"
give a similar output:
cat: no-exists: No such file or directory
bash: no-exists: No such file or directory
I'll describe the ...
- 347
4
votes
3
answers
219
views
Get Character Code for Character in File Name
Short version: I am at a bash command line. In some directory, I can ls various files and see their names. I would like to get something like the ASCII character code for each character in a file's ...
- 43
-5
votes
1
answer
86
views
To have ., the source synonym, workable [closed]
The bash' command
source
has been modified in one of few ways:
alias
function overriding
or else
Then how can its synonym:
.
got being so too (problem is it's not letter) ?
- 87
2
votes
1
answer
243
views
x2 sudo commands cannot be executed in terminal
I am running a Ubuntu system on my Radxa Zero 3E (single board computer)
Using its GPIO I am driving a 5V LED via an NPN transisitor. Everything works.
For switching it on I use gpioset $(gpiofind ...
- 323
1
vote
3
answers
183
views
Execute bash commands one at a time
I have a list of bash commands that I'd like to execute one at a time. They could be in a file, or the terminal, or whatever is necessary. But I'd like to execute the first one then I'd check the ...
- 290
15
votes
2
answers
2k
views
Why does "seq 1000000 | tee /dev/stdout" produce more single-digit numbers than expected?
I'm in Linux and in Bash. I expect
seq 1000000 | tee /dev/stdout
to always output 9 numbers from 1 to 9 and their duplicates (18 in total). But when I do
seq 1000000 | tee /dev/stdout | grep -c '^[1-...
10
votes
5
answers
610
views
Grep with output of not the complete line
With grep I can filter lines.
But if the lines are pretty long it gets messy.
How can I only get "some chars around" my search-string?
f.txt
this is a red cat in the room
this is a blue ...
- 1,049
4
votes
1
answer
835
views
Why does bash need file descriptor duplicating?
I found out I don't totally understand how bash file descriptors work. I would like to have some guidance here.
I have a scenario where I need to read the content of a file, and for each line of the ...
- 718
0
votes
0
answers
29
views
can't remove items from the bash history using a while loop [duplicate]
I have a faulty command several times in my history and want to remove it with history -d <id_of_faulty_command>.
I can identify this via a --writeout (instead of the correct --write-out)
Now ...
- 287
-1
votes
2
answers
104
views
Unix folder has file named "-f". Standard `/bin/bash` tools do not recognized this (can not `rm`, `cat`, nor `stat` this). What to do? [duplicate]
Welcome to Termux
Docs: https://doc.termux.com
Community: https://community.termux.com
Working with packages:
- Search: pkg search <query>
- Install: pkg install <package>
- ...
- 23
12
votes
2
answers
1k
views
Why arithmetic syntax error in bash causes exit from the function?
I was debugging one script, and discovered unexpected behavour of handling arithmetic syntax error.
Normally, when error happens, script is just continuing execution.
#!/bin/bash
func2 () {
echo &...
- 1,209
2
votes
1
answer
67
views
Make `set -o vi` vim cursor reflect editing mode when in `read`
I have a script read.sh:
read -ei "hello world"
eval $REPLY
Upon executing chmod +x read.sh and then running ./read.sh, I notice that pressing Esc followed by b or w jumps between the ...
- 25
0
votes
0
answers
37
views
Bash replacement with new line [duplicate]
The command echo ${PATH//:/$'\n'} should replace colons with new lines. However, I am getting spaces. What am I doing wrong here?
- 1
1
vote
2
answers
116
views
How to have bash logging ("set -x") only log the main command line (not split into pipelines)?
Consider this one-liner bash example:
$ (function test() { echo "testing a string" | grep "a" | sed 's/i/y/g'; }; set -x; test | grep "test" )
+ grep --color=auto test
+ ...
- 590
0
votes
1
answer
66
views
command line access to bash directory stack [duplicate]
In the tcsh shell, the elements of the directory stack can be access on the command line using =<#>, e,g, =0 =1 .... and a sampled command like:
cp Something =1/
would copy file Something to ...
