credentials

[default]
aws_access_key_id = default
aws_secret_access_key = meow

[miyu]
aws_access_key_id = miyu
aws_secret_access_key = meow

[myrl]
aws_access_key_id = myrl
aws_secret_access_key = meow

meh.bash

        { read -r AWS_ACCESS_KEY_ID;
          read -r AWS_SECRET_ACCESS_KEY;
        } < <(sed -n '/^\['"$AWS_PROFILE"'\]/,/^\[.\+\]/{ # Get section that starts with $AWS_PROFILE
                /^aws_access_key_id *= */s///p;           # Print AWS_ACCESS_KEY_ID
                /^aws_secret_access_key *= */x;           # Save AWS_SECRET_ACCESS_KEY
              }; $x;$s/^aws_secret_access_key *= *//p     # Print AWS_SECRET_ACCESS_KEY last
              ' < "$AWS_FILE")