{
{   The purpose of this request is to provide information maintained by the
{ access method for each file.
{
{   If this request is issued for a file which has not been previously opened
{ (FILE_PREVIOUSLY_OPENED is FALSE), the values of structural and temporary
{ attributes are taken from the following sources according to precedence:
{ <file reference> specification, SET_FILE_ATTRIBUTES command and any amp$file
{ request issued by this task. If an attribute has not been defined by one of
{ these sources, the access method will provide a default value for most
{ attributes.  An attribute for which no explicit nor default value has been
{ given will have the source component set to amc$undefined_attribute.
{
{   If this request is issued for a FILE which has been previously opened
{ (FILE_PREVIOUSLY_OPENED is TRUE), the values of structural attributes are
{ those which were preserved when the file was initially opened.  The values of
{ temporary attributes are determined as above for a file that has not been
{ previously opened.
{
{   The access method maintains information, on a file basis, which does not
{ originate from access method requests or a <file reference> specification
{ per se.  However, this information may be vital to the task accessing the
{ file.  Examples of attributes of this class are:  application_info,
{ file_length, global_access_mode, global_file_address, global_file_name,
{ global_file_position, global_share_mode, and permanent_file.  The source
{ component of these 'attributes' is set to amc$local_file_information.
{
{   This request may be issued regardless of whether the file is currently
{ open within the job.
{
{   This request only returns global file positioning information and will
{ not reflect file positioning for a file instance opened for private_read.
{
{   This request does not return values of attributes which result from an
{ amp$store request.  These values apply only to an instance of file access
{ and do not influence a subsequent amp$open request.
{
{       AMP$GET_FILE_ATTRIBUTES (FILE, FILE_ATTRIBUTES, FILE_EXISTS,
{         FILE_PREVIOUSLY_OPENED, CONTAINS_DATA, STATUS)
{
{ FILE: (input)  This parameter specifies the name of the file whose attribute
{       values are sought.
{
{ FILE_ATTRIBUTES: (input, output)  This parameter specifies one or more file
{       attributes whose value is sought.
{
{ FILE_EXISTS: (output)  This parameter specifies whether the file name
{       specified exists.  A file exists if it is in the permanent file
{       or $LOCAL catalog, or a SET_FILE_ATTRIBUTES command has been done
{       on the specified file.
{
{ FILE_PREVIOUSLY_OPENED: (output)  This parameter specifies whether the file
{       has been previously opened.  If file_previously_opened is TRUE, the
{       file's attribute definition is complete.  If file_previously_opened is
{       FALSE, a subsequent open of the file will be the initial open which
{       will result in the completion of the definition of the file's
{       attributes.
{
{ CONTAINS_DATA: (output)  This parameter specifies whether or not a file is
{       non-empty.  If the file is assigned to a terminal or a null device a
{       value of FALSE is always returned.  If the file is assigned to a
{       magnetic tape device a value of TRUE is always returned.
{
{ STATUS: (output) This parameter specifies the request status.
{       CONDITION:  ame$ring_validation_error,
{                   ame$improper_file_attrib_key.
{       IDENTIFIER: amc$access_method_id.
{
