Display output of a Bash command and keeping the output in a variable

Question

I'm not sure if it is possible but what I want to do is to run a bash command and storing the output in a variable AND display it as if I launched the command normally. Here is my code:

VAR=`svn checkout $URL`

So I want to store the output in VAR and still see the result (and because svn checkout takes a long time, I can't do echo $VAR just after..)

Thanks

score 26 · Accepted Answer · answered Jan 17 '10 at 17:15

26

If the command is run from a terminal, you can do:

VAR=$(svn checkout $URL | tee /dev/tty)

answered Jan 17 '10 at 17:15

Alok Singhal

93,253
21
125
158

2

Gah, beat me to it by seconds! – T.J. Crowder Jan 17 '10 at 17:18
1

Maybe because I tested the above with `v=$(for i in $(seq 20); do echo $i; sleep 0.2; done | tee /dev/tty)`, and you used `sleep 1`? :-) – Alok Singhal Jan 17 '10 at 17:20
1

Note that this does not work when executed by Github Actions due to the lack of a tty (see https://github.com/actions/runner/issues/241 ) – Ashutosh Jindal Aug 25 '21 at 21:57
thanks @AshutoshJindal, saved me some trouble – Lucas Ross Apr 19 '22 at 20:08

score 2 · Answer 2 · answered Jan 17 '10 at 17:50

2

You don't have to call the external tee:

VAR=$(svn checkout $URL) && echo $VAR

or even:

VAR=$(svn checkout $URL); echo $VAR

answered Jan 17 '10 at 17:50

Dennis Williamson

346,391
90
374
439

I think the idea was that `svn` takes a long time, and the OP wanted to see the output of the `svn` command in realtime, instead of after it ended. He even says so in the question :-) – Alok Singhal Jan 17 '10 at 17:55
1

I think I need to get some help on literacyoverflow! – Dennis Williamson Jan 17 '10 at 21:39

Display output of a Bash command and keeping the output in a variable

2 Answers2