How do I assign the output of a command to a variable?

Question

Is there a way to assign a value to a variable, that value which we get in terminal by writing any command?

Example command: sensors

From that we get CPU temperature. How can I assign this value to a temp_cpu variable?

This question is more suited to [su] or to [unix.se]. Try `temp_cpu=$(sensors)` (this will turn newlines to spaces, though). You can use `grep` to filter the specific info you need, too. — edwin, Jul 22 '13 at 22:16
@Tshepang, this question is not specific to Ubuntu, it's just about the *Unix-like* shell. Thus, [unix.se]. — edwin, Jul 23 '13 at 15:53
Did the policy/general opinion change? I thought this site welcomed questions that are not necessarily specific to Ubuntu. — tshepang, Jul 23 '13 at 16:55
@edwin The comments are old so you're likely aware of this, but *this is on-topic*, per [the help](https://askubuntu.com/help/on-topic), [Are non-Ubuntu-spefic questions allowed?](https://meta.askubuntu.com/q/14663), [Are “not only Ubuntu-specific” questions on-topic?](https://meta.askubuntu.com/q/14523), [How do we tell if a question belongs here, or rather at stackoverflow/superuser?](https://meta.askubuntu.com/q/47), [Are bash/shell scripting questions on topic?](https://meta.askubuntu.com/q/13807) ([related](https://stackoverflow.blog/2012/03/22/respect-the-community-your-own-and-others/)) — Eliah Kagan, Oct 11 '17 at 23:07

score 40 · Answer 1 · answered Jul 22 '13 at 22:18

Yes, you use my_var=$(some_command). For example:

$ foo=$(date)
$ echo $foo
Mon Jul 22 18:10:24 CLT 2013

Or for your specific example, using sed and grep to get at the specific data you want:

$ cpu_temp=$(sensors acpitz-virtual-0 | grep '^temp1:' | sed 's/^temp1: *//;s/ .*//')
$ echo $cpu_temp
+39.0°C

score 1 · Answer 2 · edited Jan 29 '20 at 13:20

1

You can also store the value of command as follows:

variableName=`command`
$variableName

For example:

currentDirectory=`pwd`
$currentDirectory

edited Jan 29 '20 at 13:20

Melebius

answered Jan 29 '20 at 11:56

Akshay Chopra

think code formatting on your example got lost. – Jan 29 '20 at 12:22
This works but this type of substitution cannot be nested, so [the other option](https://askubuntu.com/a/323167/250300) is preferred. @bac0n I’ve fixed the formatting problem. – Melebius Jan 29 '20 at 13:22

2 Answers2