
  This program is used to list file(s) on  a  VT100  family  terminal.
  The  file(s)  are  displayed  one screen at a time for easy viewing.
  Various commands can be entered to change listing parameters  or  to
  position  to a particular portion of the file.  Many of the commands
  are the same as the Digital editor EDT.   Commands  can  be  entered
  either by using keys on the VT100 keypad, or by entering commands to
  the prompt at the bottom of the screen.

     Help can be obtained on a particular topic by typing :
        HELP VTL subtopic subsubtopic ...

     Additional information available:

     FEATURES       INSTALLATION    GETTING_STARTED  STARTUP_OPTIONS
     COMMANDS       RANGE_FORMAT    OUTPUT_FILE      FILE_FORMATS
     ABNORMAL_TERMINATION           CONTINUATION_PROMPT

2 FEATURES
  FEATURES

    Some of the major features of the program are outlined below:

    1.  Delete the file being displayed.
    2.  Print the file being displayed.
    3.  Split screen mode to display two files.
    4.  CTRL/C detection for aborting searches, etc.
    5.  Write portions of the file being displayed.
    6.  Skipping to the next directory when using wildcards.
    7.  Displaying the file header of the file being displayed.
    8.  Teco compatible see-all mode.
    9.  Search forward/backward for a string.
   10.  Working message displayed when searching.

    Enhancments requested but not implemented yet:

    1.  Backing up to the previous file.
    2.  Swapping to auxillary file with full screen display.
    3.  Initialization file to define the keypad keys.
    4.  /FIND, /RECORD, and /PAGE options at startup.
    5.  Repetition count for commands.

    The maximum record size that can be  displayed  is  512  characters.
    All  commands have a repetition count of one.  Relative, indexed and
    stream LF files are not supported.

2 INSTALLATION
  INSTALLATION

    There are three files used  with  this  program.   The  VTL  program
    written  in Macro-11, the VTLNATIVE program written in Macro-32, and
    the error message file.  These files must be copied to the following
    directorys:

      SYS$SYSTEM:VTL.EXE - This is  the  main  program  which  can  be
      started  with  either  the  "MCR  VTL"  or  "RUN SYS$SYSTEM:VTL"
      commands.

      SYS$SYSTEM:VTLNATIVE.EXE - This program is used to  do  the  VMS
      wildcard   lookup   using   the   run   time   library   routine
      LIB$FIND_FILE.   It  is  executed  by  the  VTL   program   from
      compatibility  (PDP-11)  mode  using  the  unsupported  elephant
      directive.  This program  CAN  NOT  be  started  using  the  RUN
      command.  Obviously, this program is not needed for RSX-11M/M+.

      If the native mode routine is not located in SYS$SYSTEM,  define
      the  logical  name SYS$NORDEN pointing to the directory where it
      resides.  If the routine is not found in  either  directory,  an
      error is reported to the terminal, the user is prompted, and the
      program continues using the normal RSX-11M file lookup routines.

      LB:[1,2]RSX11M.MSG  -  This  file  contains  the  RSX-11M  error
      messages.  If the error message file is not located in LB:[1,2],
      the program  attempts  to  lookup  the  file  in  DUA0:[MILLER].
      Unfortunatly,  since  the  error  message routine uses QIO$'s to
      perform directory lookup, a logical name can not be  used.   You
      can  edit  file  RSXMSG.MAC  in  routine  GERMSG to point to any
      alternate   directory   you   want.    You   can't   specify   a
      sub-directory.

2 GETTING_STARTED
  GETTING_STARTED

    There are three methods of starting the VTL program.   The  sections
    described  below  presume  you  have the following symbol defined in
    your login command file on VMS, or VTL is installed on RSX-11M/M+:

       $ VTL :== $SYS$SYSTEM:VTL

    1.  The most common way of starting the program is to  pass  a  file
        specification  to  the  program on the command line.  When using
        this method, the file(s) specified are displayed and the program
        exits when there are no more files to display.

        Example:
             $ VTL [ROBIN...]A%C*.DAT

        Multiple  file  specifications  separated  by commas can also be
        specified.

        Example:
             $ VTL DL0:[*]*.CMD,DL1:[*]*.CMD

    2.  The second method is to allow the program to prompt for the file
        specification.   Using  this  method allows you to remain in the
        program until you type  CTRL/Z  to  exit.   After  starting  the
        program,  the  screen  is cleared and the "File(s):  " prompt is
        displayed at the bottom of the screen.  At this point, the  file
        specification can be entered.

        Example:
             $ VTL
             (The screen is cleared)
             File(s):

    3.  The last method allows you to use a command file as input to the
        program.   The  command file contains a list of all the files to
        be displayed.  This method is useful when using a  program  such
        as  "DIRECTORY"  to display all files created since a particular
        date.  The length of the command lines can be up to a maximum of
        256  characters.   The  continuation character "-" is allowed at
        the end of a line to continue the command line on the next line.
        If  the  file  extension  isn't specified the default is .CMD on
        RSX-11M and .COM on VAX/VMS.  When the end of the  command  file
        is reached, the program exits.

        Example:
             $ DIRECTORY/NOHEADER/NOTRAILER/SINCE/OUTPUT=TODAY.COM
             $ VTL @TODAY

    Once you've started displaying a file, typing the  PF2  key  on  the
    keypad  displays the keypad diagram.  There is no other online help.
    This document will be converted to the  help  file  format  at  some
    point so HELP at DCL level is possible.

2 STARTUP_OPTIONS
  STARTUP_OPTIONS

    There are a number of options which can be specified at startup time
    by  specifying  option  on  the  command  line.   The options can be
    specified anywhere on the command  line  which  allows  them  to  be
    appended  to  the  VTL symbol defined in your login command file (if
    desired).

    Options can not be specified on the command line when using  command
    file  input.  When using command file input, the options must reside
    within the command file or before the command  file  line  within  a
    command procedure.

    All options are preceded with a slash "/"  and  can  be  negated  by
    preceding  the  option  with either a minus sign "-" or a "NO".  All
    startup options can be changed after the program is started with the
    "SET"   command.   If  the  option  is  not  followed  by  the  word
    "(default)", then the  option  must  be  specified  to  enable  that
    option.  The following are the valid startup options:

    Additional information available:

    AVO       BINARY    FEXIT     FF        HEADER    LINES     MARK
    OUTPUT    NARROW    NAME      NUMBERS   PROTECT   QUIET     RULER
    SCREEN    SEEALL    SECTION   TECO      VERSION   WIDE      WAIT

3 AVO
    The  VT100 has the advanced video option.  If your VT100 doesn't
    have  the  AVO,  the  terminal  can only display 14 lines of 132
    column text.
    
3 BINARY
    When  displaying  a  binary  file,  the option suppresses escape
    seqeuences  and  all  control  characters so the text within the
    binary file can be displayed properly.

3 FEXIT
    This  controls  whether  the  program automatically displays the
    next file or exits at the end of file. If enabled, the user must
    type either "EXIT" or "NEXT" to stop displaying the current file.

3 FF
    This  controls  whether formfeeds are passed to the VT100.  This
    option is useful when the VT100 has a hardcopy attached to allow
    formfeeds to skip to the top of a new page.

3 HEADER
    Controls  whether  the  file  header  is automatically displayed
    before displaying the first page (screen) of the file.  The file
    header is displayed in a format similar to the "ANALYZE/RMS" DCL
    command.

3 LINES
    This controls the number of lines to display on the screen.  The
    default  number  of lines displayed is 20 lines if the file name
    display is enabled or 22 or it is disabled.  When operating over
    a  dialup  modem,  it is often desirable to display fewer lines.
    The  command format is "/LINES=n" where "n" can  be from 5 to 20
    (or 22 if the file name is disabled).

3 MARK
    This  command  is  used  to override how often the program marks
    record  positions.  These  record  positions are used to quickly
    reposition  to  records  within the file.  The program  has 1000
    entrys  for  saving the record positions.  If this switch is not
    specified,  the  following  algorithm  is  used to calculate the
    record marking count:

       ((blocks_used * records/block)/mark_entrys) = mark_count.

    The worst case records/block is based upon the maximum record size.

         max_record > 256 use (512/32) = 16 records/block.
         max_record > 100 use (512/16) = 32 records/block.
         max_record >  32 use (512/8)  = 64 records/block.
         max_record >  16 use (512/4)  = 128 records/block.
         max_record <  16 use (512/2)  = 256 records/block.

    The mark count is limited to a  maximum  of  50  records  unless
    overridden.  If the file you are displaying has more than 50,000
    records, you will want to specify a mark count.  Otherwise,  all
    records  after  50,000  will  have to be skipped to sequentially
    from the last record marked.  The command format is "/MARK=n".

3 OUTPUT
    This  allows  you  to  specify  an  output  file  for subsequent
    write  commands.  The  output file is not opened until the first
    write command is issued,  thus  errors  are  deferred until that
    time.  The command format is "/OUTPUT=filename". The output file
    remains open until the CLOSE command is issued or until you exit
    the program.

3 NARROW
    This  forces all files to be displayed on a  narrow  (80 column)
    screen. Normally the maximum record size within the file is used
    to determine whether the screen should be NARROW or WIDE.

3 NAME
    This  controls  whether the file name is displayed at the top of
    the  screen.  Disabling  the  file  name display allows two more
    lines for the file display.

3 NUMBERS
    This  controls  whether the record number is displayed along the
    left  hand  margin  preceeding  each display line.  These record
    numbers are useful when specifying a range for the write command.

3 PROTECT
    The  controls  whether  the  file  protection  is changed before
    deleting  a  file  using  the  DELETE command.  If protection is
    disabled,  the  file  protection  is  changed to  allow deletion
    before  deleting the file.  This is useful if you want to delete
    a  file whose protection  is  set  to  read-only  which causes a
    "Protection Violation" when trying to delete it.

3 QUIET
    This controls whether bells  are appended to messages displayed. 
    If  bells  are  disabled,  then  bells  within the file are also
    suppressed.

3 RULER
    This controls whether a ruler is displayed on the line following
    the  file  name line.  If the file name display is disabled then
    the ruler is also disabled.

3 SCREEN
    This  is  used  to  specify  the screen display  width.  It also
    controls  the number of characters displayed on each line before
    the line is truncated.  Specifying a screen width overrides  the
    NARROW or WIDE options.  The command format is "/SCREEN=n" where
    the range for "n" is from 1 to 512.

3 SCROLL
    This  controls whether both  files  should  be  scrolled when in
    split  screen mode.  This is useful when you want to do a visual
    comparison of two files.  You  can  only  scroll  in the forward
    direction  using  either  the down arrow key, section, enter, or
    the return key.  All other commands only affect the active file.

3 SEEALL
    This  allows non-printable characters such as control characters
    to  be displayed.  Control characters are displayed as ^char and
    tabs, carriage  return,  linefeed,  and  formfeed  are displayed
    by  the VT100 graphics HT, CR, LF, or FF respectivly.
    Escapes are displayed as dollar signs ($).

3 SECTION
    This  specifies  the number of  lines  advanced  by  the SECTION
    command.  The  default  section  size  is  normally  (max_lines-
    (max_lines/5)+1)  where  max_lines  depends  on  whether  you've
    specified  the /LINES options or if the you've disabled the file
    name  display.  The command format is "/SECTION=n" where "n" can
    be  any  number.  If  you  specify  zero,  the  section  size is
    calculated using the algorithm above.

3 TECO
    This  is  a  sub-option  to  the  SEEALL command.  This controls
    whether  control  characters  are  displayed  using the graphics
    character +/-char instead of the ^char format.

3 VERSION
    This displays the current version of the program.

3 WIDE
    This forces all files to be  displayed  on  a  wide (132 column)
    screen.   Normally  the  maximum  record size within the file is
    used to determine whether the screen should be NARROW or WIDE.

3 WAIT
    This controls whether the program  waits  for  a response to the
    prompt "Type any character to continue: " when a file open error
    occurs when wildcards are specified. If this option is disabled,
    the  program  waits  three seconds to give the user time to read
    the  error message displayed and then continues to open the next
    file.   This  option  is  useful when doing a wildcard list of a
    directory  which  has  files protected which normally results in
    the error "Protection Violation" being displayed.

2 COMMANDS
  COMMANDS

    There are a number of commands  available  while  a  file  is  being
    displayed.   The command prompt is displayed on the last line of the
    screen and is constructed from the last record number displayed.  If
    the  file  is positioned at the end of file, then the command prompt
    is preceeded with the string "EOF-".  Commands can also be issued by
    using  various  keys  on  the VT100 keypad.  A keypad diagram can be
    displayed by using the PF2 key.  The  keypad  commands  CAN  NOT  be
    modified  by  an  initialization  file  such as EDT keys.  The valid
    commands are described below:

    Additional information available:

    ADVANCE   BOTTOM    BACKUP    CLOSE     DELETE    EXIT      FIND
    FNDNXT    LEFT      LINE      NDIR      NEXT      PAGE      PRINT
    RIGHT     REFRESH   RESET     SELECT    SECTION   SET       SHOW 
    SHL       SHR       SPLIT     SWAP      TOP       WRITE

3 ADVANCE
    This command sets the direction to the forward direction.

3 BOTTOM
    This  command positions to the end of file and then displays the
    last part of the file on the screen.

3 BACKUP
    This command sets the direction to the backward direction.

3 CLOSE
    This  command  is used to close an output file which is open for
    the WRITE command.

3 DELETE
    This command is used to delete the current file being displayed.

3 EXIT
    This  command  is used to exit from the program or to exit split
    screen  mode  when the bottom file is active.  You can also exit
    by typing CTRL/Z.

3 FIND
    This command is used to find a search string. The command format
    is  "FIND search_string".  If  a search string is not specified,
    you are prompted for one.

3 FNDNXT
    This  command  is  used  to  find the next occurance of a search
    string.  If  a search string doesn't exist, you are prompted for
    one.

3 LEFT
    This  command moves the margin left  if  previously  moved right
    with  the  RIGHT command.  This command is equivalent to the EDT
    SHR (shift screen right) command. The command format is "LEFT n"
    where "n" is from 1 to 512.

3 LINE
    This  command is used to advance or backup a single display line
    depending of the direction.  The plus sign or minus sign is used
    to advance or backup overriding the current direction.

3 NDIR
    This  command  is used to display  the  next  directory  or sub-
    directory when wildcard directorys have been specified.

3 NEXT
    This command is used to display the next file (if any). If there
    are no further files the program exits.

3 PAGE
    This  command  is  used  to  find  the  next page.  The formfeed 
    character  defines  the  start the next page.  FORTRAN formfeeds
    and print file formfeeds are not detected (future version).

3 PRINT
    This  command  is  used to spool the current  file  to  the line
    printer.   On   RSX-11M,  the file is always spooled to LP0.  On
    VAX/VMS,  the file is spooled to SYS$PRINT which can be assigned
    to  any  line  printer.  The file is left open for display after
    the  file  is  spooled.  Thus, you must use the NEXT  command to
    display the next file if desired.

3 RIGHT
    This command is used to move the margin right to display part of
    the text  truncated  due to the terminal width.  This command is
    equivalent  to  the  EDT SHL (shift display left) command.   The
    command format is "RIGHT n" where "n" can be from 1 to 512.

3 REFRESH
    This command is used  to  refresh  the  entire screen displayed.
    The keypad is re-enabled (incase the terminal was reset) and the
    entire  screen  is redisplayed.  If two  files  are displayed in
    split screen mode, then both files are redisplayed. This command
    is used for screen refresh instead of  CTRL/W  used in EDT since
    CTRL/W is not recognized by the program.

3 RESET
    This  command  is used to reset the select range selected by the
    SELECT command.

3 SELECT
    This  command  selects a portion of the file to be written.  The
    lines  selected are displayed in reverse video just like EDT.  A
    "WRITE SELECT"  command  is  then  used  to  write  the selected
    lines.   When  this  command  is  issued  the  current  page  is
    automatically selected.  The select point starts at the  top  of
    the  current  page.  Because of this implementation, the minimum
    that can be written is a single page.   To  write  less  than  a
    page,  enable  the record number display and use a "WRITE range"
    command.

3 SECTION
    This command is used to advance or backup a section depending on
    the current direction.

3 SET
    This command is used to  change  the  listing  parameters.  This
    command is used to change  any  of the startup options described
    early plus the following commands;  SET  SEARCH EXACT or GENERAL
    (default), SET TAB n (defines the size of a tab, the default is 8).

3 SHOW
    This  command  is used to display a particular parameter.  Valid
    keywords for SHOW are:

         FILE    - Displays the file name.
         HEADER  - Displays the file header.
         KEYPAD  - Displays the keypad diagram.
         MARK    - Displays the record marking count.
         SEARCH  - Displays the search string and general/exact.
         VERSION - Displays the version number.

3 SHL
    Same as the RIGHT command.

3 SHR
    Same as the LEFT command.

3 SPLIT
    This  command  is used to enter split screen mode.  If you don't
    enter a file name on the command line, you are prompted for one.
    After the file is successfully opened, the screen is redisplayed
    with  the  file  specified  at  the  bottom  of the screen.  The
    "Active"  message is displayed to the right of the file  name to
    show  which  file  is currently active.  If commands to override
    the screen width were not specified (such as NARROW  and  WIDE),
    then  the  screen  width is controlled by the active file at the
    time the REFRESH command is executed.

    To exit from  split  screen  mode,  make  the  bottom  file  the
    "Active"  file  and  then type EXIT or CTRL/Z.  After the bottom
    screen is exited, the top file is then  redisplayed  on  a  full
    screen.

3 SWAP
    This command is used to swap between the two files displayed  in
    split  screen  mode.  The  "Active"  message is displayed to the
    right  of the active file or the "SHOW FILE" command is executed
    if the file name display is disabled.

3 TOP
    This  command  is used to positions to the top of  the  file and
    displays the first page on the screen.

3 WRITE
    This command is used to write a portion of the active file to an
    output file. If an output file is not open or you didn't specify
    an  output  file  at  startup  time  with the "/OUTPUT=filename"
    option,  you  are  prompted  for a file name.  The range for the
    WRITE command are descibed in a later section. The default range
    for the write command is "WRITE PAGE".

    If  you type the carriage return or ENTER key on the keypad, the
    program displays the next page of the file. A page is defined as
    the  text displayed on the screen as opposed to the text between
    two formfeeds as in EDT.

    You can also enter a record number at the command  prompt.  This
    allows  you to skip quickly to a position within the file.  This
    is useful if you don't know what to search for and don't want to
    repeatedly type the carriage return or section key.

2 RANGE_FORMAT
  RANGE_FORMAT

    The range for the WRITE command is a subset of the ranges allowed by
    EDT.  The normal range format is:

        beginning_line:ending_line
                or
        beginning_line THRU ending_line

    The following keywords can be used for the ranges:

        . - The ending line number on the current page.
        line_number - A line number within the file.
        BEGIN - The beginning line number of the file (line 1).
        BPAGE - The beginning line number on the current page.
        EPAGE - The ending line number on the current page.
        END - The ending line number in the file.

        PAGE - The current page displayed.  Same as BPAGE:EPAGE.
        WHOLE - The whole file.  Same as BEGIN:END.
        SELECT - The lines selected by the SELECT command.

2 OUTPUT_FILE
  OUTPUT_FILE

    The output file is created with the file type and file attributes of
    the  active  input  file.   This  means  that  if  the input file is
    variable length with print-file-format, the output file will be  the
    same  format.   This  should be rememebered when writing portions of
    multiple input file.  No checking is  done  to  insure  the  current
    input  file  attributes  are  the  same  as  the output file.  Thus,
    writing  a  FORTRAN  file   to   an   output   file   created   with
    print-file-format  will  not  PRINT or TYPE the way you expect after
    closing the output file.

2 FILE_FORMATS
  FILE_FORMATS

    Currently, only  implied  (carriage-return)  and  embedded  carriage
    control  files  are  formatted  properly for output to the terminal.
    The first character of each record in FORTRAN files and the sequence
    field used for print-files for carriage control are not interpreted.
    This support will be added in a future version of the program.

3 EMBEDDED
    For files with embedded carriage control  (carriage-return/line-feed
    in the file), scrolling backwards doesn't always backup a section or
    a single page.  This is because a single record may be displayed  on
    several  lines  on  the  screen.   To accuratly display these files,
    display the file in SEEALL mode (this is what  EDT  actually  does).
    Also,  when  scrolling  backwards  through embedded carriage control
    file, the entire screen is redisplayed since this is the only way to
    accuratly redisplay the previous page.

2 ABNORMAL_TERMINATION
  ABNORMAL_TERMINATION

    If the program aborts abnormally or by your typing  CTRL/Y  to  stop
    it,  a  software  terminal characteristic must be changed.  When the
    program starts, the escape sequence characteristic is enabled.  This
    tells the terminal driver to expect escape sequences.  By having the
    terminal driver interpret the escape sequences, the program  doesn't
    have  to  do  single  character  reads  which results in less system
    overhead (EDT does single character reads).

    The   following   DCL   command   disables   the   escape   sequence
    characteristic:

        $ SET TERMINAL/NOESCAPE

2 CONTINUATION_PROMPT
  CONTINUATION_PROMPT

    Whenever  file  open  errors  occur  with  wildcards  active,  after
    displaying  the  file  header,  or  after displaying the keypad, the
    program prompts with the message "Type any  character  to  continue:
    ".   At  this prompt, typing "E" or CTRL/Z will exit the program and
    typing "N" will display the next file.  The "N"ext feature is useful
    if you want to display just the file header (/HEADER option) of each
    file when using wildcards.
