[Help-bash] Why variables are not set in a while-read loop?

[Peng Yu]

Hi,

I thought the following two while loops are different in the sense
that the first one involves a subshell, but the second doesn't.
Consequently, I should see $file with some value printed after the
second loop but not the first loop.

However, neither of them print $file with some content. Can anybody
help me understand why? Thanks.

~$ cat main.sh
#!/usr/bin/env bash

find .. -type f -print0 | while IFS= read -r -d '' file
do
  echo "$file"
done

echo xxx $file

while IFS= read -r -d '' file
do
  echo "$file"
done < <(find .. -type f -print0)

echo xxx $file

-- 
Regards,
Peng