!Last Modified:  19-DEC-1988 11:41:44.22, By: RLB 

! EVE$FILE.TPU 			23-OCT-1987 10:27			Page 13

! Procedure called by eve_get_file to create a new buffer and map it
! to the current window.  Returns the created buffer, or zero if error.
!
! Parameters:
!	buffer_name		Name of new buffer - input
!	requested_file_name	Full VMS filespec to use - input
!	actual_file_name	From file_search; "" if not on disk - input

procedure eve$create_buffer (buffer_name,	! Create a buffer
			     requested_file_name, actual_file_name)

local   new_buffer,		! Buffer created
	create_failed,
	default_exists;

on_error
    [TPU$_DUPBUFNAME]:
	eve$message (EVE$_BUFEXIST, 0, substr (buffer_name, 1,
					       eve$x_max_buffer_name_length));
	return (FALSE);
    [TPU$_OPENIN]:
	eve$message (error_text, error);
	create_failed := TRUE;
    [TPU$_TRUNCATE]:
	eve$message (error_text, error);
    [OTHERWISE]:
endon_error;

! default buffer not created until after end of startup
! (after /INIT processing in procedure TPU$INIT_POSTPROCEDURE)

default_exists := (get_info (eve$default_buffer, "type") = BUFFER);

if actual_file_name = ""
then
    if not default_exists		! i.e., during startup
    then
	new_buffer := create_buffer (buffer_name);
	set (LEFT_MARGIN, new_buffer, eve$x_default_left_margin, CHARACTERS);
	if get_info (COMMAND_LINE, "display")
	then
	    set (RIGHT_MARGIN, new_buffer,
		 (get_info (eve$main_window, "width", CHARACTERS) -
		  eve$x_default_right_margin),
		 CHARACTERS);
	    set (RIGHT_MARGIN_ACTION, new_buffer, eve$kt_word_wrap_routine);
	endif;
    else
	new_buffer := create_buffer (buffer_name, "", eve$default_buffer);
	set (MODIFIABLE, new_buffer, ON);	! override default buffer
	set (NO_WRITE, new_buffer, OFF);	! override default buffer
    endif;
    if create_failed
    then
	delete (new_buffer);
	return (FALSE);
    endif;
    eve$message (EVE$_FILENOTFOUND, 0, requested_file_name);
    set (OUTPUT_FILE, new_buffer, requested_file_name);
else
    if not default_exists
    then
	new_buffer := create_buffer (buffer_name, actual_file_name);
	set (LEFT_MARGIN, new_buffer, eve$x_default_left_margin, CHARACTERS);
	if get_info (COMMAND_LINE, "display")
	then
	    set (RIGHT_MARGIN, new_buffer,
		 (get_info (eve$main_window, "width", CHARACTERS) -
		  eve$x_default_right_margin),
		 CHARACTERS);
	    set (RIGHT_MARGIN_ACTION, new_buffer, eve$kt_word_wrap_routine);
	endif;
    else
	new_buffer := create_buffer (buffer_name, actual_file_name,
				     eve$default_buffer);
	set (MODIFIABLE, new_buffer, ON);	! override default buffer
	set (NO_WRITE, new_buffer, OFF);	! override default buffer
    endif;
    if create_failed
    then
	delete (new_buffer);
	return (FALSE);
    endif;
    if eve$x_starting_up and get_info(command_line,"output") then 
    	set (OUTPUT_FILE, new_buffer, get_info(command_line,"output_file"));
    else
    	set (OUTPUT_FILE, new_buffer, actual_file_name);
    endif;
endif;

if not default_exists
then
    set (EOB_TEXT, new_buffer, message_text (EVE$_EOBTEXT, 1));
    set (LEFT_MARGIN, new_buffer, eve$x_default_left_margin, CHARACTERS);
    set (RIGHT_MARGIN, new_buffer,
	 (get_info (current_window, "width", CHARACTERS) -
	  eve$x_default_right_margin),
	 CHARACTERS);
    set (RIGHT_MARGIN_ACTION, new_buffer, eve$kt_word_wrap_routine);
endif;

map (current_window, new_buffer);

return (new_buffer);

endprocedure;