High Voltage Shareware/high1.zip/high1/DIR7/DLITE201.ZIP/READ.ME

Text File | 1993-08-05 | 29KB | 708 lines

                    D-LITE v2.0
         Copyright (c) 1993 Circular Logic
               all rights reserved


            Features include:


* Auto-login for Email, Forum message, and Database File transmission and
  retrieval.
* Ability to send binary files as private Email.
* SCHEDULE option for timed-delay auto-login during off-peak hours.
* PRINT option for automatically sending session download to printer.
* Multi-Forum message database for fast search and retrieval of old messages.
* Full implementation of Database cataloging, uploading, downloading, and
  updating.
* Incoming FAX viewer (a PAN FaxBox required to receive faxes online)
* Full-Featured text editor, including the ability to cut-n-paste and to view
  the original of any EMAIL message you are replying to in a "split" window.
* Zmodem, Ymodem and Kermit protocols available in addition to Xmodem.
* "Toggle" switches for full control over when to send or not send messages,
  and when to receive new messages.  All Sig Forums and Database are
  "toggleable" as well.
* Easy scanning and deleting of messages.  Message files can be
  packed after purging to reduce disk-space usage.
* Logging of session times for easy calculation of monthly usage.
* "Housekeeping" functions for deleting mail and avoiding Delphi $torage fees.
* CONFERENCE system front-end, with split-screen layout and command menus.
$ Internet Mail & FTP support.
* A myriad of bells and whistles to automate and manage messaging;
  too many to list here.



See DLITE.DOC for complete documentation.


=============================================================================
                             IMPORTANT!
=============================================================================

This is NOT a free product, nor is it public domain.  If you like it and use
it, please REGISTER.

Users have the choice of registering ONLY the current version for $29, or
opting for an "Extended Registration" for $79, which includes free upgrades
and support.

Registration details and terms can be found in the file REGISTER.TXT.

            Circular Logic
              PO Box 162
             Skippack PA 19474 USA

    Tech Support: Email to PERRY ([e-mail])
    Administration: 215-584-0300  FAX: [phone]

=============================================================================



=============================================================================
                             STARTUP
=============================================================================



Simply type DLITE to launch the program.

The first time you start D-LITE, you will be asked to enter your
"Default" settings: Your name, DELPHI username, password, etc.
Be sure to put in your full name when prompted;  D-LITE won't allow
you to skip the field, nor will it accept less than two words
(First & Last name).



=============================================================================
                 BASICS
=============================================================================

What is this anyway?

D-LITE is designed to be a ROBOT:  an automated "Front-end" and
"Auto-Pilot" that will get you online to DELPHI, send and retrieve
messages and files, and then back offline in the shortest amount of
time possible.

When you first run D-LITE, it will ask you for your "Settings" information:
your username, password, phone number to dial, etc.

After that, D-LITE is all configured to login.  However, unless you tell it to
visit some SIGS, all D-LITE will do at this point is handle Email chores.  So
one of the first things you're probably going to want to do is install some
SIGS that you want it to visit by selecting the UTILITIES menu and using the
ADD SIG option.

To install a SIG, you need to know two things:  its name, and the DELPHI
menu it is located on.  So for example, to install the PC sig, select ADD,
type "PC" (without the quotes) when prompted for a SIG Name, and select
COMMUNICATIONS from the Menu Location menu you'll see next.  Note that if you
are installing a "Custom Forum SIG", the name of the SIG is its NUMBER, so
just enter the number when prompted for a SIG Name.

Then select Automated Session from the COMMUNICATIONS Menu (or just hit F1),
and you're on your way.

It is IMPORTANT to understand that when a session starts, D-LITE is in
COMPLETE control.  Do NOT type anything into the screen.  When you see
prompts such as "What do you want to do?", DELPHI is talking to D-LITE, not to
you.  If it helps, leave the room and come back when it's finished.

The first time D-LITE goes into each SIG you've told it to visit, it will
"initialize" by setting the HIGH message pointer to the most recently-posted
message, and will download the list of "topics" to setup its internal index.
After that, each time it returns to that SIG, it will download any newly
posted messages.

If at anytime you want it to capture messages posted from an earlier period,
go to the appropriate SIGS menu, and select "OPTIONS" at the bottom of the
screen.  Then choose "Select Alternate Download Method".

Included with this file is a document called DLITE.DOC, which contains
everything you need to know about the various options available in the
program.



HINTS & TIPS
============

* The ESCAPE key is used to exit menus, and to Save or Quit message editing.

* The RETURN key is used to open any message found on a "Scan" list.

* You can edit "Pending" messages before they are sent for last minute
corrections and additions.

* If D-LITE is not picking up New Mail or downloading forum messages
that it normally does, be sure you haven't disabled on of the "toggles".
Besides having a "Master" toggle for Mail and Forum Messaging, you can toggle
individual function, such as the sending of mail, and the downloading
of new mail.  Furthermore, each SIG has individual toggles to give you
maximum control. With this capability, however, it's easy to toggle
off message reception in a particular sig, and even though your Master toggle
is ON, all subsequent sessions will ignore messages in that particular sig.
So be sure to set back any toggles you only wanted off temporarily.

* When updating Database catalogs for the first time in an area such as
the PC Sig where the database can be quite extensive, it's best to update
just one "topic" at a time.  Doing everything at once the first time may
require several megabytes of diskspace to complete.  Be prepared for some
extensive post-session processing time, depending on how fast your CPU and
hard disk is.  Normally, however, such processing is done in just a few
seconds.

* When you have new mail waiting online and have "Clear Mailbox" scheduled,
the Mailbox maintenance procedures will be disabled.

* In Conference mode, if you want to send a simple RETURN, hit the space
bar first, and then RETURN.

* If you are using D-LITE on a portable computer with a CGA video card, the
screen contrasts may seem harsh.  You can change the contrast by launching
D-LITE with a "1" parameter (e.g. DELPHI 1). This invokes and explicit MONO
screen, and the contrast should be much better.

* To disable autocapture of the each session, use ALT-L from the main menu,
or else use the NOLOG command line option.

* If you ever experience a hard crash, we suggest you run CHKDSK/F right away
when you re-boot. IF YOU ARE RUNNING WINDOWS, EXIT TO DOS BEFORE USING CHKDSK.

============================================================================
            RELEASE NOTES
============================================================================


1.0 RELEASE NOTES
=================

* Zmodem is disabled for uploads, and will default to Ymodem-Batch, which on
Delphi seems to be faster and more reliable for uploading.  Zmodem works
fine for downloading.


1.02 RELEASE NOTES
==================

* Support added for "Regional" DELPHI's (Boston, KC, etc.).
* VT52 and VT100 defaults no longer present a problem.
* SCAN NEW added to Email section to scan for new mail only.
* USAGE CALCULATOR added to keep track of online minutes.


1.03 RELEASE NOTES
==================

* Extended pathnames for file transfers now permitted.
* Added User-definable default PATH for database file downloads.
* Added a "GIMME" option to easily grab new forum messages addressed
  specifically to you.
* Forum messages and database entries can now be explicitly "saved"
  so that "purging" now leaves them intact.
* Added Threading, Print and Write (save to disk) options to Message Reader
* Fixed F5 "Save" in Email to append to existing files
* Fixed "stalling" on PC Sig default login, and on Database Updates
* ALT_P for "purging" has been changed to ALT_Z ("Zap").
* Added "Macros" to the forum/database message "Reader":


     R = REPLY when reading, or READ when scanning
     D = DELETE
     U = UN-Delete
     N = NEXT Page
     B = Go BACK 1 Page
     T = THREAD
     P = PRINT Text
     S = SAVE (i.e. Prevent text from being "Purged")
     W = WRITE (Save Message) to Disk File
     CTRL-HOME = Jump to Top of Message File

* Various "lingering" buglets squished.


1.04 RELEASE NOTES
==================

* Fixed bug that causes some messages to not be purged when using the
  "Follow Thread" option.
* Fixed bug that occassionally created a SIG called "-19.19".
* Fixed several bugs in Email that affected users whose online default menu
  is MAIN as well as certain types of reply messages.
* Fixed bug that caused an obnoxious loop when MLITE expires the demo period.
* Added a "workaround" for uninterrupted access to the BBS sig.
* Added "Housekeeping" functions (for REGISTERED users) to delete mail
  and avoid Delphi $torage fees.
* Added capability to edit SIG Names.
* Added capability to rename and/or delete Forum Topics.


1.05 RELEASE NOTES
==================

* GIMME option no longer re-sets HIGH pointer.
* Added auto-Login directly to CONFERENCE area (either Main or SIG Conference).
* Added split-screen CONFERENCE layout ... one window for input (listening),
  the other for output (talking).  Both windows have editing capabilities
  and cursor control to allow for ease of use.
* Added 16K CONFERENCE buffer that can be scrolled back and forth to review
  previous comments.
* Added major CONFERENCE commands implemented as F-keys and pop-up menus.
* Added Automatic "logging" of CONFERENCE transcript to session file.
* Added ALT_W in editor to dis-able and re-enable Delphi "wordwrap" in
  Forum Messages (.LT and .EL).
* Added additional DELETE options to Email and fixed message purge bug.
* Added "Computing" to list of SIG Menu Location choices.
* SIG Menu Locater now accepts "OTHER" to define ANY Delphi Menu location,
  so that Private SIGS and "SIGS within SIGS" can now be accessed.


1.06 RELEASE NOTES
==================

* Fixed "stubborn" disconnections.
* Fixed backspace key on manual (F2) logins.
* Fixed problem with line noise messing up Forum message files.
* Fixed problem with default download path not recognizing drive designation.
* Fixed Message limit checking in "READ FROM NNNNN".
* Fixed abrupt exits from Conference mode.
* Fixed incorrect message counter when using "FT" options.
* Added additional error traps to detect printer errors.
* Added additional usage tracking for manual (F2) sessions.
* Added support for non-standard databases.
* Added "alternative addressing" to Forum reply messages.
* Added "Carbon-Copy" capability in Email
* Added Reverse-Threading to Forum Message Reader (limited by RAM)
$ Added Creation and Maintenance of Distribution Lists to Email.
$ Added "Broadcasting" capability via Distribution Lists in Email
* Added 6 "NotePads" available from any menu via ALT-N and ALT-1 thru ALT-5.
* Added "FileSearch" function available from any menu via ALT-F.
* Added Thread "Summaries" w/ total number of replies.
* Added capability to Save, Delete, and Undelete by Thread.
* Added "Combo" login via F5: Automated session that ends in manual mode.
* Added "AutoExit" from command line.
* Added definable IRQ and Base Address options from command line.
* Added "Quiet" mode as a command line option.
$ Added advanced-user SIG-specific scripting capability.
* Added reverse scanning (bottom up) to Forum Message Reader.
* New Forum Messages to be posted are now sent BEFORE new messages are read.
* New Message Counts are now remembered after you exit MLITE.

($) = Feature can be used only by Registered-users.


1.07 RELEASE NOTES
==================

* Fixed Conference ^Z phantom.
* Fixed "flickering menu" bug.
* Added "ZERO MESSAGE COUNTER" to the UTILITIES menu.
* Added menu option for CUSTOM Forums.
* Enabled Zmodem Uploading.
* Enabled Zmodem Download Recovery.
* Enhanced Auxillary Script to support NEWS areas.
* Added command line "nolog" option to disable SESSION.TMP log file.
* Added ALT_L toggle to disable and re-enable SESSION.TMP log file.
* Program size reduced by 15K.


1.07d RELEASE NOTES
==================

* REALLY fixed Conference ^Z phantom and the "flickering menu" bug.
* Fixed problem in handling messages larger than 32K.
* INTERNET Mail is now supported.


1.08 RELEASE NOTES
==================

$ FTP options added (unregistered users can "demo" this option up to 10 times)
* Enhanced INTERNET Mail to allow subject lines and file sending
* VT100 capability added (command-line option "VT100").
* Added auto-deletion of FTP'ed files via command-line option "ZAP".
* Fixed parity problem with 9600 baud Sprintnet logins
* Fixed sporadic 'timeout' on database uploads.
* Fixed file downloading to default path on all downloads (except Mail).
* Fixed problem with setting a Base_Address for COM3 or COM4
* Program renamed from Messenger-Lite to D-LITE.


1.09 RELEASE NOTES
==================

* Message parameters now allow for more than 5 digits
* VT100 now "toggleable" with ALT-V.
* VT100 codes now stripped from SESSION.TMP
* Message Broadcast lists now support Internet addresses
* Use of low-level Update Database Catalog option now only allows cancellation
* Added startup script capability with new script commands:
  - script activated with command-line call of any ".CMD" file
  - UPLOAD will upload a file (using default file transfer protocol)
  - UPLOAD TEXT will immediately upload a text file
  - DOWNLOAD will download a file (using default file transfer protocol)
  - WHEN will wait for a prompt and issue a command (WHEN prompt action)
* Added new FTP commands (DOFTP, FTP host filename, ENDFTP) for scripting.
  (see "Enhanced Scripting Options").


2.0 RELEASE NOTES
==================

* Program re-written to remove BTRIEVE from the environment.
* Added ability to Delete SIGS.
* Forum message replies now supports auto-quoting (ALT-F9).
* "Update Topics" function no longer re-sets HIGH message pointer.
* HIGH option renamed to RESET FILE POINTER.




============================================================================
            TECHNICAL INFO
============================================================================


OVERSEAS/PTT LOGIN
==================

To login from overseas, toggle "PTT" in your default settings, and create
a "script" file as follows:

1) Create a text file called PTT.TXT.
2) To indicate time intervals, enter PAUSE or WAIT on a separate line.
   A number following the command will be translated as the number of
   seconds to wait (the default is one).  E.g.: PAUSE 3 will wait 3 seconds.
3) A blank line will send a RETURN
4) Anything else will be transmitted as a command terminated by a RETURN
5) Example:
PAUSE

.
PAUSE 2
NUI 23456778;345345
PAUSE 5
311061703093

   This script waits one second after connecting, sends <CR>.<CR>, waits
2 seconds, sends an NUI ID, waits 5 seconds, and then sends the DELPHI host
number. While it runs, each script line will appear as a "." on your
screen as it is procesed.  Upon completion, it will wait for the DELPHI
"Username" prompt to continue automatically.

Additional commands available:

LINEWAIT nnn  - forces a pause of nnn tenths of a second between lines
        when transmitting text. (Abbreviation: LW)
CHARWAIT nnn  - forces a pause of nnn tenths of a second between characters
        when transmitting text. (Abbreviation: CW)


LOG FILES
=========

Each session is completely logged to SESSION.TMP. If something should bomb out
before the program returns to your startup screen, you can see what might
have happened and recover any messages downloaded in the SESSION.TMP file.



MESSAGE FILES
=============

Incoming EMAIL messages are stored in a file called EMAIL.TXT.  Do NOT edit
EMAIL.TXT!  To reduce it's size, use the PURGE ALL option on the EMAIL menu.

"SIG" areas have two files associated with each:  *thesig*.FRM for Forum
messages, and *thesig*.DBS for Database file catalogs.  You CAN edit these
files, though if your word-processor puts an EOF (^Z) marker at the end of
a file after editing, the file will no longer be capable of holding new
messages.  To reduce their size, you must purge the file when reading with
ALT-Z or ALT-X (see the DLITE.DOC file for more details).




=============================================================================
            COMMAND LINE OPTIONS
=============================================================================

1 - Disables color for pure B&W display (useful on portables with CGA cards).

    Ex:  C> DELPHI 1

EXIT - Forces D-LITE to launch a session immediately, and then return to DOS.

    Ex:  C> DELPHI EXIT

IRQn [0xNNN] -     Tells D-LITE to use a specific IRQ and Base Address for the
        default COM port.

    Ex:  C> DELPHI IRQ3 0x2E8

QUIET - Turns off login and warning "bells".

LWnnn - forces a pause of nnn tenths of a second between lines
    when transmitting text. (Abbreviation: LW)

CWnnn - forces a pause of nnn tenths of a second between characters
    when transmitting text. (Abbreviation: CW)

NOLOG - Disables automatic session logging to SESSION.TMP

VT100 - Enables VT100 emulation.

ZAP   - Enables auto-deletion of FTP'ed files.

=============================================================================
        ADVANCED USER SCRIPT/COMMAND OPTIONS
=============================================================================

There are times during the course of a SIG Forum discussion that a long
discussion ensues that you have no interest in.  Or, there may be a particular
member or members that you don't care to read anything they might say.

Delphi's IGNORE command allows you to setup your Forum sessions to "ignore"
messages from a particular member, or on a particular subject.

To have D-LITE act on the IGNORE command, do the following:

1) Select "Use Auxiliary Script" from the OPTIONS section of the Sig you
   wish to enable scripting.

2) Enter the commands you want to be issued from the FORUM> prompt, one
   command per line.  For example, your file might look like this:

   IGNORE FROM ABBOTT
   IGNORE FROM COSTELLO
   IGNORE SUBJECT FUZZIES
   IGNORE SUBJECT "WHO'S ON FIRST"

   All commands will be sent before any messages are read, so that
   any messages that match those criteria will be ignored.

3) When you no longer want those commands to be sent during a session, turn off
   the "toggle switch" in OPTIONS that controls the "Auxiliary Script".  Or,
   erase or rename the sig's ".CMD" file.  It is important to remember that as
   long as the toggle switch is ON, the script will be acted on EVERY TIME
   until you either turn off the toggle or else erase or rename the .CMD file.

Advanced users who know how to navigate Delphi manually can use this feature
to essentially do ANYTHING by way of this simple "script", as long as you
remember that it only begins when you enter the FORUM, and if you have it
leave the Forum to do something (like check the list of POLLS, or Classifieds,
etc.) it is best to have it return to the Forum as the last command in the
file.  Otherwise, depending what else D-LITE is scheduled to do during that
session, it could get "lost in space" (ooo-eee-ooooo.....).

Additional Notes:
* A blank line appearing anywhere in the file will be sent as a RETURN (CR).
* Any line that starts with the word "REM" will be ignored, so that the file
  can include comments or "standby" commands.
* The next command in the file is sent upon returning to a ">" prompt.  If
  a prompt is not "seen" by D-LITE within 45-60 seconds, a time-out will be
  noted and command file processing will end.  Therefore, it is not
  recommended to attempt online message composition or conferencing from
  the context of a command file.
* Since at the end of the command file D-LITE resumes with the Forum "READ"
  command, you can tell D-LITE to abort reading the forum by entering "CANCEL"
  as the last line the file.  This allows you to do exotic 'reads' in the
  Forum, such as "READ NEW NS FROM BOBO SINCE 10/91", or DIR NEW IN.  Or,
  it can be used to avoid any actual forum downloading.
* One very handy use of the command file is to issue a preliminary
  "READ WAITING NS" command when entering a Forum where you expect to have
  messages waiting for you.  This will put all your new messages together
  at the top of the file.
* Note that to have any messages downloaded inserted into D-LITE's message
  files, you MUST use the "NS" or NONSTOP command.  Otherwise, anything
  download can be retrieved from the sig's ".TMP" file.  If you wish to
  save anything in the .TMP file, be sure to do so before the next D-LITE
  session, as the .TMP file is overwritten everytime D-LITE enters the SIG.

Here's an extended example of a command file.  Comments are in parentheses.


IGNORE FROM PERRY       (no sense reading my own stuff)
IGNORE SUB ABORTION     (enough already!)
REM DIR WAITING         (in case I want a directory of waiting messages)
READ WAITING NS         (read new messages addressed to me)
DIR NEW IN              (scan a directory of newly-posted threads)
WHO              (check and see who is online now in the sig)
REM QUIT         (used instead of EXIT to keep HIGH pointer unchanged)
EXIT
POLL              (go into POLL)
LIST              (list all Polls)
/LEN 20          (set 20 line screen display)
GO NEWS UPI INT      (scan the last 20 headlines on UPI International Wire)
EXIT
NAT              (scan the UPI National Newswire)
EXIT
/LEN 0          (set screen length to zero to avoid "more?" prompts)
GO PC FORUM          (needed to return to Forum or if Database is scheduled)
CANCEL          (explicitly end command file to avoid READ NEW NS,
             unless the "Get Messages" toggle is OFF).



=============================================================================
                         STARTUP SCRIPTS
=============================================================================

To execute a startup script, create a file with the ending ".CMD",
and pass it as a command line parameter.  For example, if the
file is called LOGIN.CMD, type DELPHI LOGIN.CMD to start the program.

The following special commands are available within the script:

  UPLOAD filename       uploads the specified file
  UPLOAD TEXT filename  uploads the specified file specifically as TEXT.
  DOWNLOAD filename       downloads the specified file
  WHEN prompt action    makes D-Lite wait for a specified prompt, and then
            gives a specified command response (action).
  REM comment        allows you to put remarks in the script that
            are ignored when the script is execute.

Other than these special commands, anything you type on a line will
be sent to DELPHI as a command.  If you leave a blank line, a single
RETURN will be sent.

Also see the section on ENHANCED FTP SCRIPTING for additional script
options available for FTP access.



=============================================================================
                NOTEPADS
=============================================================================

From any menu, or from within the Forum Message reader, hit ALT-N to open
a "notepad".  Five other notepad files can also be opened (one at a time)
by using ALT-1 thru ALT-5.



=============================================================================
                             USING FTP
=============================================================================

To use FTP, login real-time.  Once online, press ESC and use option #6.
Enter the host address you want to go to when prompted.  Then wait
till the window pops open and you see the FTP> prompt.

NOTE: D-LITE auto-senses if you're already on an FTP host and opens the
window without first prompting you for a host name.  The FTP option will
also work on ANY host, even if you didn't first login to DELPHI to connect.
To use it in this manner, use the "Modem Window" on the UTILITIES menu.

Use the UP/DOWN cursor arrow keys to postiong the file or directory
you want.  If it's a directory, D-LITE will switch to it for you.  If it's
a file, D-LITE will give you a few options, and then "Get" it for you.

When you exit the FTP host, D-LITE will ask you if you want to download
the files you just retrieved, and if you want to auto-logoff afterwards.

If you want D-LITE to automatically delete FTP'ed files after they are
downloaded from DELPHI, use the ZAP command line option on startup.

VT100 is now a startup option, enabled with the command-line VT100 command.



=============================================================================
                     ENHANCED FTP SCRIPTING OPTIONS
=============================================================================


    DOFTP  - signals D-Lite that an FTP session is about to begin.

    ENDFTP - signals D-Lite that all FTP activity is ended, and
         downloading should begin.

    FTP host [filename] - tells D-Lite to connect to a specified and get a
         specified filename.  Note that the filename is optional, so
         that the command can be used to simply connect to a host and
         await subsequent commands.

-------------------------------------------------------------------------
Example of how to automate an FTP file transfer from a startup script.
In this example, the script will login to myhost.edu and get /pub/readme,
then return to DELPHI and download the files.

DOFTP
FTP myhost.edu /pub/readme
ENDFTP

or

DOFTP
FTP myhost.edu
CD pub
FTP myhost.edu readme
ENDFTP

If the above example were stored in a file called FTPTEST.CMD, then
you would launch D-Lite by typing "DELPHI FTPTEST.CMD" to have the
script acted on.  What you name the file doesn't matter, as long as
the filename ends with ".CMD".

Note: Do not use the GET command unless you do not want D-Lite to
attempt a download afterwards.  You must use "FTP host filename" if
you want D-Lite to automatically retrieve the files.

-------------------------------------------------------------------------

Example of how to automate an upload of a file called "WHATEVER.ZIP"
to your workspace.

WORKSPACE             (gives Delphi the WORKSPACE COMMAND)
WHEN WS> ZUP WHATEVER.ZIP    (gives Delphi the ZUPLOAD command)
WHEN ?                 (send a RETURN when it sees a "?")
UPLOAD WHATEVER.ZIP        (Tells D-Lite to upload the file)

-------------------------------------------------------------------------



=============================================================================
                             IMPORTANT!
=============================================================================

This is NOT a free product, nor is it public domain.  If you like it and use
it, please REGISTER.

Users have the choice of registering ONLY the current version for $29, or
opting for an "Extended Registration" for $79, which includes free upgrades
and support.

Registration details and terms can be found in the file REGISTER.TXT

            Circular Logic
              PO Box 162
             Skippack PA 19474 USA

    Tech Support: Email to PERRY ([e-mail])
    Administration: 215-584-0300  FAX: [phone]

=============================================================================




                          DISCLAIMER

Use at your own risk.  D-LITE is available on an as-is basis.  No warranties
express or implied including without limitation those of merchantability and
fitness for a particular purpose are made with respect to D-LITE.

Circular Logic will not be responsible for DELPHI downtime, idiosyncracies, or
subsequent changes made to the DELPHI host system that may adversely affect
the performance of D-LITE.

DELPHI is a trademark of General Videotex Corporation.  PAN, PAN FaxMail,
The Messenger, MLITE, Messenger-Lite, and D-LITE are trademarks of
The PAN Network and its subsidiary, Circular Logic.