Category "bash"

How do I escape a series of backslashes in a bash printf?

The following script yielded an unexpected output: printf "escaped slash: \\ \n" printf "2 escaped slashes: \\\\ \n" printf "3 escaped slashes: \\\\\\ \n" prin

Concatenating variables in Bash [duplicate]

I am trying to add a variable to the middle of a variable, so for instance in PHP I would do this: $mystring = $arg1 . '12' . $arg2 . 'endoffi

Copy current command at bash prompt to clipboard

I would like a quick keyboard command sequence to copy the current command at a bash prompt to the clipboard. So that, for example, to copy the last bash comm

How to detect array start index by current shells (zsh/bash)?

We all know arrays in Bash are indexed from zero, and in zsh are indexed from one. How can the script know it should use 0 or 1 if I can't ensure the running en

How to detect array start index by current shells (zsh/bash)?

We all know arrays in Bash are indexed from zero, and in zsh are indexed from one. How can the script know it should use 0 or 1 if I can't ensure the running en

Windows PATH to posix path conversion in bash

How can I convert a Windows dir path (say c:/libs/Qt-static) to the correct POSIX dir path (/c/libs/Qt-static) by means of standard msys features? And vice vers

How to use sed to remove the last n lines of a file

I want to remove some n lines from the end of a file. Can this be done using sed? For example, to remove lines from 2 to 4, I can use $ sed '2,4d' file But

How to use sed/grep to extract text between two words?

I am trying to output a string that contains everything between two words of a string: input: "Here is a String" output: "is a" Using: sed -n '/Here/,/

How to export an associative array (hash) in bash?

Related, but not a duplicate of: How to define hash tables in Bash? I can define and use a bash hash, but I am unable to export it, even with the -x flag. For

How not to pass the locale through an ssh connection command

I have some aliases for ssh, example: alias buildWork="ssh work '~/build_app'" The problem is that the ssh command passes some variables like $LC_CTYPE that ca

How to prevent docker container from stopping after executing sh script file

im running a docker container as shown below, after the sh files are executed the container terminate by default, how i can keep the container working in backgr

I just assigned a variable, but echo $variable shows something else

Here are a series of cases where echo $var can show a different value than what was just assigned. This happens regardless of whether the assigned value was "do

How to extract last part of string in bash?

I have this variable: A="Some variable has value abc.123" I need to extract this value i.e abc.123. Is this possible in bash?

Pipe a vim command after a shell command

I'm trying to make a key mapping in vim that (a) saves current file (b) performs a git action, using shell (c) quits current vim editor. I've tried the followi

how to generate core file in docker container?

using ulimit command, i set core file size. ulimit -c unlimited and I compiled c source code using gcc - g option. then a.out generated. after command ./a.o

Bash variable substitution and strings

Let's say I have two variables: a="AAA" b="BBB" I read a string from a file. This string is the following: str='$a $b' How to create a new string from the

Use a variable's value in a sed command [duplicate]

I can't seem to use a variable in a sed command, for example: sed "24s/.*/"$ct_tname"/" file1.sas > file2.sas I want $ct_tname the varia

Add shell or bash to a docker image (Distroless based on Debian GNU/Linux)

I want add shell or bash to my image to execute installation command. I have copied the /bin/bash on my VM on to my image on Dockerfile: COPY /bin/bash /bin/

How to output a multiline string in Bash?

How can I output a multipline string in Bash without using multiple echo calls like so: echo "usage: up [--level <n>| -n <levels>][--help][--versio

Postgres - testing database connection in bash

I wonder if there is an alternative to the psql command to test the connection to a postgresql database using bash. I'm setting up a Core OS cluster and have a