{
{   The purpose of this procedure is to return the current segment length
{ to the caller.
{
{        MMP$GET_SEGMENT_LENGTH (PVA, VALIDATION_RING_NUMBER, SEGMENT_LENGTH,
{          STATUS)
{
{ PVA: (input) This parameter specifies the segment for which the current
{        segment length is returned.
{
{ VALIDATION_RING_NUMBER: (input) This parameter specifies the ring number
{        used for validation if it is greater than the caller ring number.
{
{ SEGMENT_LENGTH: (output) This parameter is where the current segment
{        length is returned.
{
{ STATUS: (output) This parameter is where the request status is returned
{        to the caller.  The possible error codes are:
{              mme$caller_not_in_read_bracket
{              mme$invalid_pva
{              mme$ref_to_unrecovered_file
{              mme$segment_number_not_in_use
{              mme$segment_number_too_big
{

