on Bash

on the case statement
to have glob separator-safe to assign arrays like ( *glob* ), do shopt -s nullglob

**working with file descriptors**
for i in "${descriptors[@]}"; do exec {i}<&-; done for i in "${!descriptors[@]}" do exec {descriptors["$i"]}<&-; done	close file descriptors
exec {descriptors["$index"]}<"$filename"	open file descriptors into empty array
test -t	tests if it's a terminal, don't confuse
[[ -v "descriptors['$index']" ]] && while read -u ${descriptors["$index"]} -r do echo "$REPLY" done; >&2 echo We\'re at EOF	(better make sure the element exists) read from file descriptor default variable is REPLY read non-zero when EOF mostly