CP/M/CPM_CDROM.iso/cpm/xccp/xccp.doc

Text File | 1994-07-13 | 12.1 KB | 367 lines

                                       X C C P

                                     Version 1.0
                        An Extended Console Command Processor
                                         for
                                       CP/M-80



        1.0 INTRODUCTION

        XCCP  is  a  substitute console command processor  (CCP)  for  Digital
        Research  Inc.'s CP/M-80 operating system.   XCCP provides  additional
        functions  not provided in the "stock" CP/M CCP at the expense of  the
        loss of a small portion (1 Kbyte) of the transient program area (TPA).
        The memory lost in this way is not usually important on systems having
        64K bytes of memory.


        1.1 ADDED FUNCTIONALITY

        XCCP  provides the following features not provided by the  distributed
        CP/M CCP.


        1.1.1 COMMAND RECALL

        Up  to  approximately  240  characters of  previous  commands  may  be
        recalled for re-issue with a single keystroke.


        1.1.2 COMMAND LINE EDITING

        Both  recalled commands and newly entered commands may be edited using
        cursor  control  keys  and  dual  mode  (insert/overstrike)  character
        insertion.  Characters may be deleted anywhere on the command line.


        1.1.3 COMMAND RECOGNITION

        A  list of possible commands or filenames matching a  partially  typed
        command  line  can  be  displayed  with  a  single  keystroke  without
        destroying  the current command.   No more aborting a command to  list
        your directory because you forgot an obtuse filename.

        If  no command has been started,  a list of all possible commands that
        may be issued from the current user area is displayed.


        1.1.4 COMMAND COMPLETION

        If  a  partially  typed command has only a  single  possible  matching
        command or filename,  the rest of the command may be filled in on  the
        command line automatically, in most cases eliminating the need to type
        long commands out in their entirety.








        1.1.5 WILDCARD RECOGNITION

        Filenames  on the command line may contain  wildcard  characters,  and
        with a single keystroke,  all possible matches can be displayed.  This
        is  useful,  for example,  if you have forgotten the  file  name,  but
        remember the file type.  If only one match is found, it is inserted on
        the command line in place of the wildcarded filename.


        1.1.6 MULTIPLE COMMANDS PER LINE

        Multiple  commands,  up to 127 characters,  may be issued on a  single
        command  line  for sequential execution by separating  the  individual
        commands with a special delimiting character.


        1.1.7 AUTOMATIC SEARCH OF DISK A USER AREA 0

        If  a  command is not found in the current user area,  user area 0  on
        disk A is automatically searched.


        1.1.8 DISK AND USER SPECIFICATION

        Changing  user  area and disk are accomplished with the  same  syntax,
        eliminating the need for the cumbersome USER command.  Additionally, a
        user number may optionally be included in the command (with or without
        a  disk  designator),  causing that user area to be searched  for  the
        command instead of the current user area.


        1.1.9 NO INVOLUNTARY WARM RESTARTS

        Return  to  the CCP from an application program is much  faster  under
        XCCP,  since  warm restarts are only performed upon  user  request.  A
        control-C may be entered at any time,  even in the middle of a command
        line,  resetting  the  disk system without disrupting the  command  in
        progress.


        1.1.10 EXIT TO STANDARD CP/M CCP

        A single keystroke returns control to the standard CCP,  although this
        is  unlikely to be desirable except when it is necessary to perform  a
        SAVE operation.


        1.1.11 USER NUMBER DISPLAYED IN PROMPT

        The current CP/M user area number is displayed in the XCCP prompt as a
        constant reminder.










        2.0  XCCP COMMANDS

        To  invoke XCCP,  simply type XCCP as you would for any CP/M  program.
        Optionally, an XCCP command line may be included in the invocation.

        Example:       A>XCCP B15:;FIND MAST.LST MDM712


        2.1 RECOGNITION AND COMPLETION

        The  ESC (Escape,  ASCII 27 decimal) key may be used whenever you  are
        unable  to  recall the exact spelling of a  command  or  filename,  or
        simply to avoid typing long commands or filenames in their entirety.

        After  ESC is entered,  the characters on the command line between the
        cursor  and  the  first  preceeding space are used  to  search  for  a
        matching  file  on the appropriate disk and user (Disk A,  user  0  is
        searched if the characters being used for the match are the first word
        of the command line).   If more than one file is found,  the  matching
        files  are listed,  and the command redisplayed for user  action.   If
        only  one match is found,  the command is filled in with that file  or
        command.   The  cursor is left at the end of the command,  for further
        user input.  You may hit RETURN at this point to issue the command.


        2.2 COMMAND RECALL

        Commands are maintained in a circular buffer in memory.  That is, when
        the end of the list is reached, the next command displayed will be the
        first  one again.   The WORDSTAR arrow keys (^E for  uparrow,  ^X  for
        downarrow)  are  used to move about within the recall command  buffer.
        The  uparrow  will  redisplay commands  issued  before  the  displayed
        command,  while  the downarrow will display commands issued after the
        command currently displayed.   In both cases, if the end of the buffer
        is reached, the cycle simply starts over.

        If,  after  perusing  the recall command buffer,  you can't  find  the
        command  you  want,  and  none of the ones there are close  enough  to
        warrant editing,  you can cancel the currently displayed command  with
        ^U.

        2.3 COMMAND LINE EDITING

        The  WORDSTAR arrow keys (^S for leftarrow and ^D for rightarrow)  can
        be  used  at any time to move the cursor about on  the  command  line.
        Once  the  cursor is positioned,  characters may be entered in  either
        overstrike or insert mode.   The initial mode is overstrike.   The  ^V
        key  is used to toggle the editing mode between overstrike and  insert
        (as  in WORDSTAR).

        When the cursor is not at the end of the command line, both the delete
        and  backspace  keys will remove the character which is at the  cursor
        position,  appearing  to "gobble up" the command line to the right  of






        the  cursor.   When the cursor is at the end of the line,  these  keys
        remove the character to the left of the cursor, allowing easy deletion
        of mistyped characters.



        2.4 MULTIPLE COMMANDS PER LINE

        Multiple  commands  may be entered on a single line by separating  the
        commands  with  a semicolon character.   When the carriage  return  is
        struck, the commands will be executed in the order issued.  There MUST
        NOT  be any spaces between the semicolon and the characters on  either
        side of it.



        2.5 DISK/USER SPECIFICATION

        If a disk and/or user specification of the form du:  is prefixed to  a
        command (the first word of the command line or after a semicolon), the
        specified  disk and/or user area is searched for the .COM file  before
        A0:.   Either  or  both  the disk letter and user area number  may  be
        included in the command this way.   File specifications on the command
        line MUST NOT have user area numbers,  although disk designations  are
        allowed, as in CP/M's standard CCP.

        Example:       A6:WS C:TEST.DOC is acceptable to XCCP, while

                       A6:WS C2:TEST.DOC is not.


        If the du: designation is entered alone on a command line, the default
        disk and/or user area is changed.

        2.6 WARM BOOT

        The  effects  of a CP/M warm boot may be achieved through the  use  of
        CTRL-C.   This  results in a reset of the disk I/O subsystem,  and  is
        likely to be necessary after changing floppy disks.   This function is
        normally done on most program exits, resulting in a delay in return to
        the CCP prompt.  By making this function user requested, return to the
        CCP  prompt  on program exit is much faster with XCCP  than  with  the
        stock CCP.


        2.7 EXIT TO CP/M CCP

        Entering  CTRL-Y  in  response to the XCCP  prompt  will  restore  the
        original CP/M CCP.


        2.8 COMMAND CANCELLATION

        An  entire  command line may be revoked before issuance  with  the  ^U
        character.








        2.9 WILDCARD USE

        The  wildcard  translation feature of XCCP may be used  to  determine,
        before execution of a program,  just which files will be affected by a
        command.  For example, if the command ERASE *.HEX were terminated with
        an  ESC rather than a carriage return,  a list of the files which  are
        about  to  be  deleted would be displayed,  allowing the user  a  last
        chance to abort the command before issuing the carriage return.

        Note that incomplete file specifications, such as T*.A, are treated as
        if   they  ended  with  wildcards  (T*.A*),   due  to  XCCP's  command
        recognition/completion algorithm.  Thus, in this case, more files than
        will actually be affected by the command may be displayed  (e.g.  both
        TEST.A and TEST.ASM would be displayed).



        3.0 LIMITATIONS AND CONSTRAINTS

        A  number  of features of the standard CP/M CCP were left out in  this
        first version of XCCP in order to avoid increasing XCCP's size  beyond
        what could be easily tolerated in a 64 Kbyte system.


        3.1 NO SUBMIT

        The CP/M SUBMIT command will not function under XCCP.   Use ^Y to exit
        to the standard CCP before using SUBMIT.


        3.2 NO SAVE

        There is no SAVE command in XCCP.   Use ^Y to exit to the standard CCP
        before using SAVE.  ^Y does not alter the contents of TPA memory.


        3.3 NO BUILT-IN COMMANDS

        The  CP/M  CCP's  commands DIR,  REN,  ERA,  USER,  and TYPE  are  not
        available in XCCP.   Transient programs are included with XCCP to take
        the place of REN and ERA.   USER is supersceded by superior facilities
        within XCCP, and a great number of DIR and TYPE programs are available
        in the public domain.


















        4.0 VERSION 2.0

        Version  2.0  of XCCP is expected to include a CP/M-compatible  SUBMIT
        facility  (all  your existing .SUB files will  work)  with  additional
        features such as internal variables, conditional branching, and nested
        procedures.   Also planned for V2.0 are I/O redirection (like UNIX and
        MS-DOS's  <,  >,  and | operators),  key redefinition (as in  QwikKey,
        Smartkey, etc.), and hierarchical directory support.  These additional
        features  will  not  increase the size of XCCP,  since  they  will  be
        implemented  as overlays.   The functions chosen for implementation in
        overlays  were  chosen with a view toward which functions  access  the
        disk in any case, and those functions which are the least utilized.