git-bisect: weird usage of read(1)

Hello

I found this in git bisect:

              printf >&2 'Are you sure [Y/n]? '
              case "$(read yesno)" in [Nn]*) exit 1 ;; esac

which looks very weird since read(1) returns a status and not the
string reads from std input.

Am I missing something ?

Thanks
-- 
Francis