This variable controls the behavior of ACCEPT FROM INPUT STATUS when the input is
not attached to a terminal. If SCRIPT_STATUS has its default setting "0" (off, false, no), an ACCEPT FROM INPUT
STATUS statement returns a fixed value when the program has redirected input. The
value returned is the value of the INPUT_STATUS_DEFAULT variable.
When SCRIPT_STATUS is not "0", and input is redirected, then ACCEPT FROM INPUT STATUS
returns the actual status of the script file (i.e., it returns "1" (on, true, yes)
unless the script file has been exhausted).