Why Bash redirection order matters
Bash applies redirections from left to right. If opening an input file fails before stderr is redirected, Bash writes the open error to the original stderr.
read -r value < "$file" 2>/dev/null # Input open happens first
read -r value 2>/dev/null < "$file" # Stderr is redirected first
When a file may be missing and you want to hide Bash's open error, place 2>/dev/null before the input redirection. This changes where the diagnostic goes, not the command's exit status. It is not a universal “all output redirects first” rule; redirections run left to right, so their order determines which destination is active when each one is applied.