{   The purpose of this procedure is to allow permanent file manager to perform
{ cleanup of the permanent file environment that is maintained between calls to
{ other permanent file procedures.  This procedure must be called at a point in
{ time when no further permanent file activity is to occur within the job and
{ while the permanent file tables are still usable.
{
{       PFP$PROCESS_JOB_END (RETURN_FILES_OPTION)
{
{ RETURN_FILES_OPTION: (input, output)  This parameter specifies whether files
{   should be returned as a result of this request.
{   On a single mainframe the return of files should have been accomplished
{     by the fmp$job_exit request, so there is no need to return them now.
{   On the file server this request may be used when the client mainframe
{     has terminated abnormally and it is desired to cleanup up that mainframe's
{     environment on the server.  On the server a call to
{     pfp$set_task_environment must be performed first.
{     return_files specifies whether to return files.
{       log_returned_files:  This indicates whether the names of files that
{         were returned should be recorded in the system and job logs.
{       wait_for_down_volume
{       IF TRUE then the permanent file manager will wait for
{         the volume to come online before returning files on a down volume.
{       IF FALSE then all files that can be returned will be returned and
{         the files_on_down_device count will indicate how many files
{         are left attached because they reside on a down device.
{       For the file server it is suggested that the first call not wait for
{       down volumes, so that as many files be returned as possible.  It is
{       suggested that on the second pass that wait is specified.
