Print string variable that stores the output of a command in Bash

Question

I need to place the output of a command in Bash into a string variable.

Each value should be separated by a space. There are many options to do that but I cannot use mapfileor read options (I'm using Bash < 4 version in macOS).

This is the output of the command:

values="$(mycommand | awk 'NR > 2 { printf "%s\n", $2 }')"

where mycommand is just a cloud command that gets some values like:

echo $values

mycommand output: (which I think is a string ending with \n for each value)

55369972
75369973
85369974
95369975

This is what I'm trying to do:

Here I should print the values like (I need to iterate over the variable values so I can print each value individually).

desired output in the foor loop

value: 55369972
value: 75369973
value: 85369974
value: 95369975

but I'm getting this:

value: 55369972 75369973 85369974 95369975

# Getting the id field of the values
values="$(mycommand| awk 'NR > 2 { printf "%s\n", $2 }')"
# Replacing the new line with a space so I can iterate over each value
new_values="${values//$'\n'/ }"
# new_values=("${values//$'\n'/ }")
# Checking if I can print each value correctly
for i in "${new_values[@]}"
# for i in "$new_values"
do
  echo "value: ${i}"
done

Also, I cannot use things like

# shellcheck disable=xxx
values=($(echo "${values}" | tr "\n" " "))

As I'm getting error messages when checking the code...

Any idea what I'm doing wrong in my code?

Answer 1

try this:

#!/bin/bash

values="$(mycommand | awk 'NR > 2 { printf "%s\n", $2 }')"
for v in $values; do
  echo value: $v
done

Answer 2

Since I can't paste code into the comments, I post an answer but the credits go to @akathimy above.

This works for me (solution #1):

#!/bin/bash
# Getting the id field of the values
values="55369972 75369973 85369974 95369975"
# 
for v in $values; do
  echo value: "$v"
done

and this also (solution #2):

#!/bin/bash
# Getting the id field of the values
values="55369972
75369973
85369974
95369975"
# 
for v in $values; do
  echo value: "$v"
done

Edit: And what about this one (solution #3)? :

#!/bin/bash
# Getting the id field of the values
values=("55369972
75369973
85369974
95369975")
# 
for v in ${values[@]}; do
  echo value: "$v"
done

This last one works for me, and perhaps also for you. Let me know.

Answer 3

Your step that replaces the newlines with spaces renders it as a string. If you want to split that string into a list, you should put it in brackets (based on this answer )

This should do what you are expecting:

# Getting the id field of the values
values="$(mycommand| awk 'NR > 2 { printf "%s\n", $2 }')"
# Replacing the new line with a space
new_values=("${values//$'\n'/ }")
# Checking if I can print the values correctly
for i in ${new_values}
do
  echo "value: ${i}"
done

where new_values=("${values//$'\n'/ }") is the crucial part, then you need to avoid putting it in quotes when you iterate it (or you turn it back into a string)