How to store the output of a command in a variable at the same time as printing the output?
Use tee to direct it straight to screen instead of stdout
$ var=$(echo hi | tee /dev/tty)
hi
$ echo $var
hi
Pipe tee
does the trick.
This is my approach addressed in this question.
var=$(echo "hello" | tee /dev/tty)
Then you can use $var
to get back the stored variable.
For example:
var=$(echo "hello" | tee /dev/tty); echo "$var world"
Will output:
hello
hello world
You can do more with pipes, for example I want to print a phrase in the terminal, and at the same time tell how many "l"s are there in it:
count=$(echo "hello world" | tee /dev/tty | grep -o "l" | wc -l); echo "$count"
This will print:
hello world
3
Send it to stderr.
var="$(echo "hello" | tee /dev/stderr)"
Or copy stdout to a higher FD and send it there.
$ exec 10>&1
$ var="$(echo "hello" | tee /proc/self/fd/10)"
hello
$ echo "$var"
hello