{
{   The purpose of this request is to switch to the next volume of a file.
{ This request has meaning only for files assigned to magnetic tape devices.
{ It is ignored for files assigned to other device types.
{ The identity of the next volume is determined from the ordered list of
{ volumes supplied with a REQUEST_MAGNETIC_TAPE command or rmp$request_tape
{ program interface.
{
{   If the preceding operation was an output and the label_type is
{ amc$labelled, the standard ANSI EOV labels are written.  If a
{ label_exit_procedure(*) was specified, control passes to this procedure for
{ user label processing.  For all label_type values, two tapemarks are then
{ written to terminate the volume.  The next volume is then obtained.  If the
{ label_type is amc$labelled, the standard ANSI VOL and HDR labels are
{ written.  If a label_exit_procedure(*) was specified, control passes to this
{ procedure for user label processing.  A single tapemark is then written
{ after the HDR label group.  For an unlabelled or non standard labelled file,
{ the tape is positioned at the beginning of the volume.
{
{   If the file is being read, the next volume is obtained.  If the label_type
{ is amc$labelled, the standard HDR labels are validated by the access method.
{ If a label_exit_procedure(*) was specified, control passes to this procedure
{ for user label processing.  The file is then positioned after the tapemark
{ following the HDR label group.  For an unlabelled or non standard labelled
{ file, the tape is positioned at the beginning of the volume.
{
{   This request does not invalidate the file_identifier.  Therefore, the file
{ need not be reopened subsequent to this request.
{
{       AMP$CLOSE_VOLUME (FILE_IDENTIFIER, STATUS)
{
{ FILE_IDENTIFIER: (input)  This parameter specifies the file access
{       identifier established when the file was opened.
{
{ STATUS: (output) This parameter specifies the request status.
{       CONDITION:  ame$accessibility_conflict,
{                   ame$block_type_conflict,
{                   ame$file_set_id_conflict,
{                   ame$fsn_out_of_sequence,
{                   ame$improper_access_level,
{                   ame$non_ansi_labels,
{                   ame$record_type_conflict,
{                   ame$ring_validation_error,
{                   ame$section_out_of_sequence,
{                   ame$tape_end_of_volume_list,
{                   ame$unrecovered_write_error.
{       IDENTIFIER: amc$access_method_id.
{
