I'm trying to use an array with while read, but the entire array is output at once.
#!/bin/bash
declare -a arr=('1:one' '2:two' '3:three');
while read -e it ; do
echo $it
done <<< ${arr[@]}
It should output each value separately (but doesn't), so maybe while read isn't the hot ticket here?
For this case, it is easier to use a for loop:
$ declare -a arr=('1:one' '2:two' '3:three')
$ for it in "${arr[@]}"; do echo $it; done
1:one
2:two
3:three
The while read approach is very useful (a) When you want to read data from a file, and (b) when you want to read in a nul or newline separated string. In your case, however, you already have the data in a bash variable and the for loop is simpler.
while read would mean taking it out of the bash variable as a string which read would then reprocess into new bash variables. I'm sure that there are cases where that is useful but they would be quite rare.
-d flag with read to set the delimeter. But this is NOT recomended. ss64.com/bash/read.htmlpossible by while loop
#!/bin/bash
declare -a arr=('1:one' '2:two' '3:three');
len=${#arr[@]}
i=0
while [ $i -lt $len ]; do
echo "${arr[$i]}"
let i++
done
With the Bash script below you should achieve what you want.
#!/bin/bash
# Ensure fail-fast script execution.
shopt -os nounset pipefail errexit errtrace
declare -a arr=('1:one' '2:two' '3:three');
while read -r it; do
echo "${it}"
done < <(printf '%s\n' "${arr[@]}")
A couple of things to note here:
shopt -os.it because you're not interacting with the terminal while the script is running.read its -r option.printf '%s\n' statement prints each array element on a new line. The output printf produces is then directly fed via the standard input stream into the while loop.
cat <<< ${arr[@]}puts all elements on the same line.<and<<also, but didn't really get it.