I have a simple function that colors its input argument.
color_text_red()
{
echo -e "\033[0;91m$1\033[0m"
}
Now, I have 2 variables START_COUNT and STOP_COUNT that have some value.
START_COUNT="1"
STOP_COUNT="2"
I would like to construct the string [1, 2] where 1, 2 is colorized. So, I did this :
out_res="${START_COUNT}, ${STOP_COUNT}"
echo "[$(color_text_red $out_res)]"
Sadly, this outputs only [1,].
Why $STOP_COUNT is missing ?
Observe:
f() {
echo "First argument: $1"
echo "Second argument: $2"
}
var="a b"
f $var
It will output:
First argument: a
Second argument: b
The unquoted variables are splitted using whitespace characters (tabs, newlines and spaces) and then passed to the function (that is, assuming IFS variable is the default or unset). So, if the variable has spaces, it will be splitted. That's why it is adviced all over stackoverflow to quote your variables.
You should quote your variable expansions if you want to pass only a single argument to the function:
out_res="${START_COUNT}, ${STOP_COUNT}"
echo "[$(color_text_red "$out_res")]"
Rule of a thumb: always type " in front and after $ expansions, ex. "$var" or "$(echo 1)" or "${var## }".
Some additional read: bash manual word splitting, riptutorial word splitting.
color_text_red $out_res- because you are passing two arguments to the function.$out_res. How can we achieve this otherwise ?