done < <(cmd)to redirect from process substitution (currently missing one
sum=0 while IFS="" read -r n do (( sum += n )) done <(file)
sum=0 while IFS="" read -r n do (( sum += n )) done < <(file)
ShellCheck found a
done keyword followed by a process substitution, e.g.
The intention was most likely to redirect from this process substitution, in which case you will need one extra
done < <(cmd).
This is because
<(cmd) expands to a filename (e.g.
/dev/fd/63), and you need a
< to redirect from filenames.
ShellCheck is a static analysis tool for shell scripts. This page is part of its documentation.