Linux Question
bash read returns with exit code 1 even though it runs as expected
I have this construct to initialize a variable with the contents of a file:
echo "yyy" > xxx
read -r -d '' PAYLOAD <<< $(cat xxx)
echo $?
echo $PAYLOAD
This results in:
1
yyy
Why is read returning 1? This is breaking my script, because I run with
set -e
Answer Source
read is returning 1 because it returns 0 only when end-of-file is not encountered.
As per help read:
Exit Status:
The return code is zero, unless end-of-file is encountered
You don't even need a read here, just use $(<file) to read the file content into a variable:
echo "yyy" > xxx
payload=$(<xxx)
echo $?
echo "$payload"
It is advisable to not use all uppercase variable names in order to avoid clash with ENV variables.