How do you store the output of a command in a variable bash?

How do you store the output of a command in a variable bash?

Bash Assign Output of Shell Command To And Store To a Variable

1. var=$(command-name-here) var=$(command-name-here arg1) var=$(/path/to/command) var=$(/path/to/command arg1 arg2)
2. var=`command-name-here` var=`command-name-here arg1` var=`/path/to/command` var=`/path/to/command arg1 arg2`

What is $1 $2 in bash script?

$1 is the first command-line argument passed to the shell script. Also, know as Positional parameters. $0 is the name of the script itself (script.sh) $1 is the first argument (filename1) $2 is the second argument (dir1)

How do I run a bash script from the command-line?

Make a Bash Script Executable

1. 1) Create a new text file with a . sh extension.
2. 2) Add #!/bin/bash to the top of it. This is necessary for the “make it executable” part.
3. 3) Add lines that you’d normally type at the command line.
4. 4) At the command line, run chmod u+x YourScriptFileName.sh.
5. 5) Run it whenever you need!

How to read each line of command output in Bash?

Using readarray in the bash shell, and GNU sed: readarray -t my_array < < (my_command | sed ‘1~2d’) The built-in readarray reads the lines into an array. The lines are read from a process substitution.

How to assign each line of command output to values?

Using readarray in the bash shell, and GNU sed: The built-in readarray reads the lines into an array. The lines are read from a process substitution. The sed command in the process substitution will only output every second line read from my_command (and could also be written sed ‘1!n;d’, or as sed -n ‘n;p’ with standard sed ).

How to apply shell command to each line?

I want to apply a command (say echo) to each one, in turn. E.g. echo a echo b echo c echo d echo e What’s the easiest way to do that in bash? It’s probably easiest to use xargs. In your case: The -L flag ensures the input is read properly. From the man page of xargs: -L number Call utility for every number non-empty lines read.

Do you have to use another line in Bash?

Another pitfall with this is that command substitution — $ () — strips trailing newlines. Probably not always important, but if you really want to preserve exactly what was output, you’ll have to use another line and some quoting: