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                    Backdoor Reference Manual - Version 1.0 








                           Intrinsic Computer Systems 
                                  29 Ridge Road 
                              Oak Ridge, NJ   07438 
                                (201) 697 - 0174 



















2
.h :...Backdoor Reference Manual - Version 1.0
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.f :...Page $$$
                                    LICENSE 


     All versions of Intrinsic's Backdoor are not public 
     domain software, nor are they free software. 


     Backdoor is copyright (C) 1988,1989 by Intrinsic 
     Computer Systems 

     Non-registered users are granted a limited license to use 
     Backdoor on a trial basis for the purpose of determining 
     whether the program is suitable  for  their  needs.  Use of 
     Backdoor,  except for this limited purpose,  requires  
     registration.  Use  of  non-registered  copies  of Backdoor 
     by any person,  business,  corporation, governmental agency 
     or other entity institution is strictly forbidden. 

     Registration permits a user the license to use Backdoor. 
     A registered user may use the program on a different 
     computer, but may not use the program on more than one 
     computer at the same time. 

     No user may modify Backdoor in any way,including but not  
     limited to decompiling, disassembling or otherwise  
     reverse engineering the program. 

     All users are granted a limited license to copy Backdoor 
     only  for  the trial  use  of  others subject to the above 
     limitations,  and also the following: 

     Backdoor must be copied in unmodified form,complete with the  
     file containing this license information. 

     Any and all Backdoor documentation must be included with the 
     copy. No fee, charge or other compensation above a nominal 
     distribution charge may be accepted or requested. If any 
     distribution fee is charged it must not exceed $5 per disk. 

     Backdoor may not be distributed in conjunction with any  
     other product. 
     
3
     Operators of electronic bulletin board systems (Sysops) 
     may post Backdoor for downloading by their users only as  
     long  as  the  above conditions are met. 

     Distributors of public domain or user supported  
     software may distribute copies of Backdoor subject to the  
     above conditions only after  obtaining written permission  
     from Intrinsic Computer Systems.  Such permission usually is 
     granted. Please write or call for details. 

     See  the  Ordering  section  for  more  information  on  
     registration, corporate licensing and similar topics. 
4

                                   WARRANTY 

     Intrinsic Computer Systems makes  no  warranty  of  any  
     kind, express  or implied,  including without limitation,  
     any warranties of merchantability and/or fitness for a 
     particular  purpose.  Intrinsic Computer Systems shall not 
     be liable for any damages,  whether direct,  indirect,  
     special or consequential arising from a failure of this 
     program to operate in the manner desired by the user.  
     Intrinsic Computer Systems shall not be liable for any 
     damage to data or property which may be caused directly or  
     indirectly  by use  of  the program. 

     IN  NO  EVENT WILL Intrinsic Computer Systems  BE LIABLE TO 
     YOU FOR ANY DAMAGES,  INCLUDING ANY LOST PROFITS,  LOST 
     SAVINGS  OR  OTHER INCIDENTAL  OR  CONSEQUENTIAL  DAMAGES  
     ARISING  OUT  OF  YOUR  USE OR INABILITY TO USE THE PROGRAM, 
     OR FOR ANY CLAIM BY ANY OTHER PARTY. 
5

         Intrinsic Computer Systems             Order Form(BD1.0) 
                 29 Ridge Road 
             Oak Ridge,NJ   07438 
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6
L---+---T1----+-T--2----T----3--T-+----4T---+---T5----+-T--6----R----7--T-+---
                       CHAPTER Quick Start 

Welcome to Backdoor.  To allow you to install Backdoor as quickly 
as possible, simply follow the directions below. If you feel, 
after reading them, that you need more detailed instructions then 
turn to Detailed Installation Directions. This will lead you 
through the installation in a more thorough manner. 


Step 1: Install Backdoor onto your hard disk into the 
        subdirectory you wish to keep Backdoor in. 

        b) Copy the files from the Backdoor diskette into the 
           Backdoor subdirectory: 

        copy a:Backdoor.* 

Step 2: Run Backdoor 

        a) Type 

        Backdoor 

Step 3: Press the key labeled "Alt" and the "h" 
        simultaneously. These are the Backdoor hot key 
        combination.  

Step 4: Review the hardware settings for Backdoor. 

        a) Use the down arrow key to move the highlighted 
        cursor bar to "Hardware Setup" and press the 
        return key. 

        b) Look at the hardware settings presented. Make 
        sure your modem is connected to the 
        communications port number ("Com Port") as 
        displayed. Also, verify the baud rate,data 
        bits,parity, and stop bits.  

        c) If you need to change one of the hardware 
        settings, press the down arrow key to move the 
7
        cursor bar between the various hardware settings. 
        When the setting you wish to change is 
        highlighted, press the return key and enter the 
        correct hardware setting. Finish entering your 
        change by pressing the return key. 

        d) To save the configuration, press the ESC key to 
        exit to the main menu. Move the cursor bar to 
        "Config Save" and press the return key.  The 
        hardware configuration will be saved. 

Step 5: Explore! Call up the other windows and see how they 
        work. 
   
        Some Hints: 

        a) At any of the menus in Backdoor you can obtain 
        help by pressing the F1 key.  A help window will 
        pop up to explain the various options available 
        to you. 

        b) When the main menu displays you may go directly 
        to a selection by pressing the first letter of 
        the selection. 
8
                     CHAPTER Introduction 

Thanks for purchasing Backdoor!  Backdoor is a file transfer and 
terminal emulation program.  It works with Hayes compatible 
modems and supports three widely used file transfer protocols 
(Xmodem, Kermit, and Ymodem). It supports baud rates of up to 
19,200. It has an ANSI compatible terminal emulator.  

Backdoor will automatically schedule file transfers to other 
Backdoor'd computer systems. You can set up Backdoor to answer 
your phone and receive a file in the file transfer protocol of 
your choice. It also, has an extensive logging facility.   

It does all the above while you may be running,say, any 
spreadsheet or word-processing package. While running your other 
application, you may optionally have Backdoor inform you progress 
of file transfer or you may directly call backdoor up to use 
Backdoor's other features directly. 

The rest of this manual is divided into sections which describes 
each of these features as available from the main menu of 
Backdoor.  Once Backdoor's installed its main menu may be called 
up by pressing the "hot key" combination.  The default hot key 
combination is "alt h." 

If  you have  any  comments  concerning  Backdoor they would be 
greatly appreciated and can be sent to us via the above address 
or via CompuServe.  Our CompuServe identification number is 
[75036,1602]. Please let us know what you are doing with 
Backdoor, what applications, what hardware, etc.  The better we 
know you the better we can tailor our product to your needs.  
Drop us a line with a return address, phone number, business 
card, and brief description. 
9
                CHAPTER Transfer Status Window 

This window's used to see the statistics of the current file 
transfer and do some infrequent Backdoor operations. From this 
window you may cancel the current transfer, toggle the top of 
screen status bar, and remove Backdoor. 

The Transfer Statistics Displayed are: 

File Name: Contains the current file name being sent or 
        received. If no file is transferring then this field will 
        be blank 

Bytes Xfrd: Contains the accumulated bytes transferred for the 
        current file.  If the current protocol is Kermit this 
        byte count will accumulate to a larger number than the 
        actual file size.  This is because Kermit uses a special 
        encoding scheme that translates binary characters into 
        two ASCII characters. 

Last Msg: May contain a text message describing the last error 
        condition that has occurred.  Depending on the nature of 
        the message the error my mean the current transfer is in 
        the process of aborting, or merely that a minor error 
        occurred and an attempt has or will be made to recover. 
        The list of error messages and their probable cause and 
        meaning is in the appendix. 

File Xfrd so far: This field has the accumulated count since 
        Backdoor has started of files transferred. 
        
File Xfrd since last check: This field has the accumulated 
        count since you last called up this menu of files 
        transferred. 

        Actions you may do while viewing this window. 

Cancel Xfer: By entering a 'Y' in this field you will force 
        Backdoor to cancel the current file transfer. Press the 
        return, then press the 'Y' key.  If you wish to escape 
        without entering a 'Y', either press the 'N' key or press 
10
        the ESC key. 

Remove Backdoor: By entering a 'Y' into this field you will 
        force Backdoor to attempt to remove itself from the 
        computers memory.  You may wish to do this before running 
        large application programs or programs that may conflict 
        with Backdoor.  Please note that you cannot remove 
        Backdoor from memory if it's not the last installed TSR, 
        nor can you remove Backdoor if you are running an 
        application program. 

        To remove Backdoor move the highlighted arrows to this 
        field and press the return key. Then press the 'Y' key. 
        If you wish to escape without entering  'Y', either 
        press the 'N' key or press the ESC key.  If you enter 'Y' 
        Backdoor will display a warning window.  This warning 
        window will prompt you to press a key.  Once you press a 
        key,if Backdoor can remove itself it will remove       
        its windows, if not it will display an error message. 

Status Bar: By entering a 'Y' into this field you will allow a 
        status bar to display at the top of the screen. This 
        status bar shows the current file name transferring, the 
        number of bytes transferred, a status code (see 
        appendix), and the protocol in use. If you enter a 'N' 
        into this field the status bar will not display. 

        To change the status bar display status move the 
        highlighted arrows to this field and press the return 
        key. Then press the 'Y' or 'N' depending if want a status 
        bar or not. If you wish to escape without changing the 
        current setting either press the 'N' key or press the ESC 
        key.  
11
                       CHAPTER Misc Setup Window 

This window's used to set your autoanswer protocol type, the 
directory to place received files into, the directory from which 
files to send out from, and the key combination to start up 
Backdoor.  You may wonder why the send/receive directories must 
be specified. The reason is, that since Backdoor is running in 
the background while an application is active, the current 
directory may be changed without Backdoor noticing it.  If the 
current directory changes Backdoor may lose a file its in the 
process of transferring. Therefore, a fixed directory must be 
used by Backdoor. 


A change to the hot key field does not come into effect unless 
you save the current configuration (See Main Menu Save Config 
choice).  The other fields changes do not become permanent unless 
you save the current configuration, but they do become the 
current until you remove Backdoor or reboot your computer. 


        The Misc Setup Fields are: 

Receive Directory: This field shows the current directory that 
        will receive files. To change the directory, move the 
        highlighted arrows to this field and press the return 
        key. Then enter the directory name that you wish to use 
        for received files.   If while entering the directory 
        name you wish to escape without changing the current 
        setting press the ESC key.  When you do enter a directory 
        name Backdoor will check to see if the directory exists. 
        If it doesn't Backdoor will present an error window 
        informing you of this.  Protocol: This field shows the 
        current default protocols for receiving a file. To change 
        the default protocol move the highlighted arrows to this 
        field and press the return key. Then enter the protocol 
        name that you wish to use for received files.  You may 
        use the up/down arrow keys to  have Backdoor present the 
        different protocols available if you choose.  

        If while entering the default protocol you wish to 
12
        escape without changing the current setting press the ESC 
        key.  When you do enter a directory name Backdoor will 
        check to see if the protocol is a valid one. If it isn't 
        Backdoor will present an error window informing you of 
        this, and revert to using the previous entry of this 
        field. 

Send Directory: This field shows the current directory that 
        will be used to send files. To change the directory, move 
        the highlighted arrows to this field and press the return 
        key. Then enter the directory name that you wish to use 
        for sending files. 

        If while entering the directory name you wish to escape 
        without changing the current setting press the ESC key.  
        When you do enter a directory name Backdoor will check to 
        see if the directory exists. If it doesn't Backdoor will 
        present an error window informing you of this, and revert 
        to using the previous entry of this field.  


Hot Key: This is really two fields.  You can use this field to 
        change the hot key combination that will start Backdoor.  
        This may be needed if Backdoor's hot key combination 
        conflicts with other TSR programs. Once this field 
        changed, the hot key combination will not come into 
        effect until you save the current configuration, remove 
        Backdoor and restart it. 

To change the hot key combination, move the highlighted 
        arrows to either one of these fields and press the return 
        key.  You may use the up/down arrow keys to have Backdoor 
        present the different hot keys available.   Or you may 
        enter directly in the hot key name that you wish to use 
        for starting Backdoor. 
13
                 CHAPTER Upload Setup Window 

In this window you set up for files to be automatically uploaded 
to other computers using Backdoor. In each row of this window you 
enter the date/time, the telephone number to call, the 
communications settings, and the filename to send. 

In this window by pressing the down arrow key the highlight 
arrows will highlight the entire row. If you press the down arrow 
until the highlight bar reaches the bottom of the window and 
continue to press down, more rows will scroll up.  To modify 
fields within a row press the right arrow, or the return key. 
Then move the highlight arrow to the field you wish to change. 

The Upload Setup Fields are: 

Date:   This is actually three fields next to each other. The 
        fields are in month,day, and year order. To change the 
        date, move the highlighted arrows to either one of these 
        fields and press the return key. Enter directly in the 
        number you wish to use. 

        When you do enter a date Backdoor will check to see if 
        the date is in the future. If it isn't Backdoor will 
        present an error window informing you of this, and revert 
        to using the previous entry of this field.  

Time:   This is actually two fields next to each other. The 
        fields are in hour - minute order. To change the time, 
        move the highlighted arrows to either one of these fields 
        and press the return key. Enter directly in the number 
        you wish to use. 

        When you do enter a time Backdoor will check to see if 
        the time is in the future. If it isn't Backdoor will 
        present an error window informing you of this, and revert 
        to using the previous entry of this field.  

Baud:   In this field you put in the baud rate of the receiving 
        computer. Please note that your modem must also support 
        this baud rate.  Most modems support a range of baud 
14
        rates, and most will automatically adjust downward to the 
        incoming modem's. You must enter the baud rate that will 
        be used during the transfer of files, not the baud rate 
        the other computer will 'answer' at. 

        To change the baud rate move the highlighted arrows to 
        either one of these fields and press the return key. You 
        may use the up/down arrow keys to have Backdoor present 
        the different baud rates available.  Or,you may enter 
        directly in the number you wish to use. If while entering 
        the number you wish to escape without changing the 
        current setting press the ESC key.  When you are finish 
        entering the baud rate press the return key. 

        When you do enter a baud rate Backdoor will check to see 
        if the baud rate is valid. If it isn't Backdoor will 
        present an error window informing you of this, and revert 
        to using the previous entry of this field.  

D, P, & S fields: These fields are the Data Bits, Parity, and 
        Stop bit fields.  Usually, these are 8,N, & 1. However, 
        some computer systems set them differently so be safe and 
        ask. 

        To change the these fields move the highlighted arrows to 
        either one of these fields and press the return key. You 
        may use the up/down arrow  keys to have Backdoor present 
        the different possible field contents available.  Or,you 
        may enter directly the text you wish to use. If while 
        entering you wish to escape without changing the current 
        setting press the ESC key. When you are finish entering 
        press the return key. 

Protocol: In this field you enter the file transfer protocol to 
        use to send the file. To change the protocol, move the 
        highlighted arrows to this field and press the return 
        key. Then enter the protocol name that you wish to use.  
15
        You may use the up/down arrow keys to have Backdoor 
        present the different protocols available if you choose.  

        If while entering the protocol you wish to escape 
        without changing the current setting press the ESC key.  
        When you do enter a protocol name Backdoor will check to 
        see if the protocol is a valid one. If it isn't Backdoor 
        will present an error window informing you of this, and 
        revert to using the previous entry of this field. 

Telephone #: In this field you enter the telephone number of 
        the other Backdoor computer. To change the telephone 
        number, move the highlighted arrows to this field and 
        press the return key.  Then enter the telephone number 
        that you wish to use. 

        If while entering the telephone number you wish to 
        escape without changing the current setting press the ESC 
        key. 
        
Filename: In this field you enter the filename to send to the 
        other Backdoor computer. To change the filename, move the 
        highlighted arrows to this field and press the return 
        key. Then enter the file name you wish to send. If while 
        entering the filename you wish to escape without changing 
        the current setting press the ESC key. 
16
                  CHAPTER Hardware Setup Window 

In this window you set up the hardware settings for your 
communications port.  The communications port is how the IBM PC 
talks to your modem. Your modem is how your computer interfaces 
to the telephone system and finally to the other computer. 

The Hardware Setup Fields are: 

Com Port: The communication port is usually 1 or 2. If you have 
        an internal modem the port the port number must still be 
        set as the modem itself looks like a port to Backdoor. 

Baud Rate: The baud rate field should match the baud rate of 
        the modem you will be using.  Usually, this will be 2400 
        baud.  However, baud rates from 300 to 19,200 baud are 
        supported. The faster the baud rate the more pauses you 
        will notice during a file transfer since Backdoor is 
        working with a higher volume of data. 

Data Bits: This field is usually 8 and refers to the number 
        of bits per character of data sent over the serial port 
        or modem.  The reason you may wish to change this is that 
        this setting should match the data bits of the modem or 
        computer system you will be connecting to.  Some systems 
        use 7 data bits.  To be absolutely sure of what the data 
        bits are, ask the owner of the other system. 


Parity:	This field refers to weather if any modem error 
        detection is done.  There is no real standard setting for 
        this.  It is possible to connect to another computer at a 
        different parity setting but usually the file transfer 
        will not work. 

Stop Bits: This field is usually 1 and refers to the number 
        of bits that indicate the end of a character.  

17
Modem Init String: The modem initialization string usually 
        begins with "AT."  The actual string depends on the modem 
        type.  Backdoor, supports Hayes or Hayes-compatible 
        modems only.  Fortunately, most intelligent modems are 
        Hayes compatible.  If you are using the modem at home the 
        string should be ATD.  The "AT" is the modem attention 
        string, the "D" is the modem dial command.  Backdoor uses 
        this string to issue dial commands to the modem. 

        If you are using this on a telephone system where you 
        need to dial a number to get to an outside line the modem 
        string should look something like this "ATD9."  Where the 
        digit "9" would be replaced by the actual number you need 
        to dial out with.  If you intend to only dial long 
        distance numbers then you may append the digit one onto 
        modem string.  If you wish to dial long distance and 
        local numbers do not put in the long distance 
        prefix in this field. Prefix all your telephones (in 
        other Backdoor fields) with a one. 
18
                   CHAPTER Config Save Window 

Choosing this option will save the current configuration. The 
current configuration is : 

        Dial Number (As used in Terminal Mode) 
        Hardware Settings (Defined in Hardware Setup) 
        Hot Key Combination (Defined in Miscellaneous Setup) 

        Modem Init String (Defined in Hardware Setup) 
        Protocol (Defined in Miscellaneous Setup) 
        Receive Directory (Defined in Miscellaneous Setup) 
        Send Directory (Defined in Miscellaneous Setup) 
        Status Bar (Y/N) (As defined in Transfer Status) 
19
                   CHAPTER Save Schedule Window 

When this option's selected the current schedule as setup in 
upload setup is saved.  Next time Backdoor is loaded it will load 
in the schedule. If the scheduled has any files scheduled for a 
future time Backdoor will send them at the scheduled time. 
20
                   CHAPTER Review Log Window 

When this option's selected you may review Backdoor's log file. 
This log file contains status messages written by Backdoor. Each 
message is date and time stamped so you can see when the message 
was written.  To review the file, simply press any key and it 
will scroll through the log file. Press the ESC key to exit. 

 
Messages are written on the following condition. 

        Abort of a file transfer 
        End of a file transfer 
        Start up of a file transfer 
        Time Out 
        Unable to open file 
21
              CHAPTER Virtual Terminal Window 

When this choice's selected a partial screen virtual terminal 
will appear.  This terminal emulation is a subset of an ANSI 
terminal. It supports simple cursor movement, line and screen 
clears. 
 
The terminal mode is usually a window that you can "pop"up on the 
screen that will act like a "dumb" terminal. Characters received 
during terminal mode while the terminal window is not up are 
saved in an internal buffer.  So, when you call up the terminal 
window you will see the characters received since you last looked 
at the terminal window. 

One important note about terminal mode is that upon calling up 
the virtual terminal you remain in terminal mode until the hang-
up key is pressed.  Even if you exit, the virtual terminal (Alt-
x) you will be still in terminal mode. If you are in terminal 
mode you cannot automatically receive file transfers from other 
Backdoor systems - you must press the hang-up key combinations 
(Alt-h). 

While in terminal mode the following special keys are defined: 

        Key          Description 

        Alt-d           Dial a number 
        Alt-e           Echo characters 
        Alt-g           Capture screen 
        Alt-h           Hang-up phone 
        Alt-k           Script invocation 
        Alt-p           Change port settings 
        Alt-x           Exit 

While in terminal mode you may start a file transfer by pressing 
the PAGE UP or PAGE DOWN keys for sending or receiving. 


Press the Alt-X key combination to exit the terminal mode.  


22
Press the Alt-G key combination to capture a copy of the terminal 
screen to a Backdoor.SCR file. 


Press the Alt-P key combination to change the current port or its 
settings (baud rate, parity, etc.).  

To have Backdoor "echo" characters as typed in, press Alt-E 
combination. 

To dial out press the Alt-D combination and enter the telephone 
number to dial, or on a Hayes' compatible modem type ATDXXXXXXX 
where X is the telephone number. 

To hang-up and exit the terminal into modem mode, press Alt-H. 
Hanging-up is the only way to exit from the terminal mode into 
the modem mode. 


Alt-k is used to start a script file up.  Type in the full name 
of the script file including extension. To abort or exit a script 
file, press the ESC key. Script file commands are described in 
the appendix. 
23
                  CHAPTER  How To Set Up For Autoanswer 

When Backdoor is loaded it automatically sets up the modem for 
autoanswer. Then Backdoor goes into "Modem" mode.  You can see 
what mode Backdoor is in by looking at the status bar.  When 
Backdoor is in modem mode it will continuously wait for a 
character to be received on the port.  Once it detects a 
character it will go into the default receive protocols' receive 
sequence.  For Xmodem this means, that Backdoor will start 
sending a NAK character. 

When in modem mode Backdoor will wait for the telephone to ring 
(assuming you have a modem), and then enter into receiving a file 
when the other system "connects" with your modem. 

Warning!  When you start up the virtual terminal from the menu, 
Backdoor exits the modem mode and enters the "terminal" mode.  To 
restore the modem mode from the terminal mode, simply hangup 
(alt-h) will in the virtual terminal. Backdoor will change the 
mode to modem. 

The reason the modem mode is lost once you enter the terminal 
mode is that once you enter the terminal you may wish to maintain 
it in that mode( even if you resume working on your foreground 
application). Backdoor has no way of "knowing" what your 
intentions are and therefor we designed it such that you have to 
explicitly tell Backdoor. 
24
                  CHAPTER Detailed Installation Directions 


These detailed instructions are for installing Backdoor onto your 
hard disk. 

Step 1: Boot up your computer: 


Step 2: Next at the DOS prompt create  the Backdoor 
        subdirectory on your hard disk.  The Backdoor 
        subdirectory name may be of your own choosing or 
        even an existing one. However, we recommend that 
        Backdoor be put in its own subdirectory if for no 
        other reason but to keep it separate. Once you 
        choose where in your hard disk's directory structure 
        to put the new directory, move to its parent's 
        directory via DOS's CD command and use the following 
        DOS command to create the new directory: 

                mkdir Backdoor 

Step 3: Next move to the new directory by typing: 

                cd Backdoor 

Step 4: Copy the files from the Backdoor diskette (we assume 
        its in the A drive) into the Backdoor subdirectory 
        by typing the following command: 

                copy a:Backdoor.* 

Step 5: To Run Backdoor type: 

                Backdoor 
25
                        APPENDIX 

                    How Backdoor Works 

Backdoor belongs to a class of programs called "Terminate and 
Stay Resident (TSR)".  It installs itself and becomes part of 
your computers, memory - not permanently though! 

Backdoor works in the "background" while another program is 
working in the "foreground." This "background/foreground" stuff 
merely means that while a program you are using is running, 
Backdoor is periodically run.  

Backdoor, when it does run, usually runs for only a few tenths of 
a second.  However, depending on such things a whether you're 
doing a file transfer, how fast your disk and computer are, 
Backdoor will consume more time.  This may be as much as a few 
seconds.  

During these occasions the computer may appear to pause.  Don't 
worry! Backdoor is merely do something in the "background" and 
will return the computer to the "foreground" application as 
quickly as possible. 
26
                        APPENDIX Scripting 

Scripting's intended to allow you to create script files for 
automated sign on to the remote systems that you use. To create a 
script file use your word processor (in its straight ASCII mode) 
or EDLIN (comes with DOS). 

Script file commands are very simple and will work in 95% of all 
cases.  The commands may be upper or lower case, and may have 
leading white space. You may also have blank lines. 

The commands are as follows: 

WAITFOR "XXXXXXXXXXXXXXXXXXXXXXX" 

Where "XXXXX..." is the string to wait for. Control characters 
are denoted by preceding them by the caret '^' symbol. For 
example to wait for "USERNAME:" where there is a carriage return 
after the user name string use the following: 

        WAITFOR "USERNAME:^M"   

Please note the quotes around user name are part of the syntax of 
WAITFOR and must be included. If part of the string you wish to 
wait for has a double quote character then put two double quotes 
in the string. 
  
WAIT NNNN 

Waits for NNNN seconds. Pauses execution of a script file for 
NNNN seconds.  You cannot escape from this command.  This command 
is useful in situations where a pause may occur on the other 
system.  You therefore may wish to wait for a few seconds. 

As an example to wait for 300 seconds (5 minutes) the command 
would be: 

        WAIT 300 


27
SEND "XXXXXXXXXXXXXXXX..........X" 

This command sends the string "XXXXXXXXXXX...X" to the remote 
string.  The string may contain control characters as the WAITFOR 
string can.  As an example to send a password sign on the 
following might be sent: 

        SEND "YOURNAME^N" 


DIAL NNNNNNNNNNN 

This command dials the number NNNNNNN. Note the NNNNN number may 
contain commas or dashes.  For example to dial the long distance 
number 201-430-7700 the following would be used: 

        DIAL 1-201-430-7700 


# 

This command simply allows comments be inserted in your script 
files.  Any text on the same line, following the pound sign will 
be ignored. 
28
                APPENDIX Error Codes and Messages 

The following is a list of the possible error numbers that will 
appear on the top of screen bar, and the corresponding error 
message in the status window.  Under each message is a brief 
explanation of what it means and possible causes and corrective 
actions (if necessary). 

 Error     Message 

 
  1     Record header mismatch            
 

        During a file transfer the header of a packet had a 
        mismatched sequence number. 

 
  2     CRC error                         
 

        During a file transfer the CRC check failed for a 
        packet. 

 
  3     Buffer full                       
 

        During a file transfer the internal buffer of Backdoor 
        filled up. This means that Backdoor didn't have a chance 
        to empty its buffer to disk.  A possible reason is that 
        the foreground program was doing extensive disk activity 
        (such as formatting a disk). Or that the directory that 
        Backdoor puts it files to is full or inaccessible (does 
        Backdoor think its directory is on a floppy which is no 
        longer in the floppy?) 

 
  4     Buffer empty                      
 

  
29
 
  5     Invalid record header             
 

        During a file transfer a packet was received with an 
        invalid record header. 

 
  6     Time out                          
 

        During a file transfer the other side failed to send a 
        recognizable packet or did not send any packet at all 
        during a fixed period. 

 
 7     Xfer aborted by other end         
  

        During a file transfer the transfer was aborted by the 
        other computer.  This may have occurred because of the 
        other side not having enough disk space or by the other 
        sides operator. 

 
  8     Can't open file - Fatal           
 

        During a file transfer Backdoor was unable to open the 
        file it was to send or unable to open the file it was 
        creating( during a receive). 

 
  9     Can't write file - Fatal          
 

        During a file receive Backdoor was unable to write to the 
        file. This may be because of the disk is full or Backdoor 
        is unable to access the file (floppy door open?). 

30
 
 10     Port hardware error               
 

        This occurs when a parity error, overrun, or framing 
        error's detected on the port.  Corrective action is 
        sometimes unnecessary since errors due occur on telephone 
        lines.  If this error is recurring rapidly such as 
        several times a second, then probably your port hardware 
        settings (or the other computers) is incorrect. 

 
 11     Invalid packet type - Fatal       
 

        During a file transfer (usually a Kermit transfer) a 
        packet was received whose packet type wasn't expected.  
        This usually suggests a severe synchronization problem 
        exists between the two computers and therefor is 
        irrecoverable. Backdoor will send an abort file transfer 
        to the other computer. 

 
 12     Unable to synch up - Fatal        
 

        At the beginning of a file transfer Backdoor was unable 
        to start the exchange of file packets. 

 
 13     Record out of sequence - Fatal    
 

        During a file transfer Backdoor got a packet with a 
        sequence number out of order.  This usually suggests a 
        severe synchronization problem exists between the two 
        computers and therefor is irrecoverable.  Backdoor will 
        send an abort file transfer to the other computer. 

31
 
 14     Communication Interrupt Stolen    
 

        When Backdoor starts up it re-vectors the communications 
        ports interrupt to itself.  If while Backdoor is in the 
        background another communication program is run in the 
        foreground, the foreground program will re-vector the 
        communications interrupt to itself.  Backdoor will detect 
        this and while the foreground communications program is 
        actively using the communications interrupt Backdoor will 
        do nothing (other than show this error code).  After the 
        foreground program releases the communications interrupt, 
        Backdoor will re-vector the interrupt to itself. 

 
 15     Transferred OK 
 

        At the end of a successful file transfer, Backdoor will 
        show this message. 

 
 16     Packet Resent 
 

        If during a file transfer a minor error's detected, the 
        usual course of action is to resend the packet. 
        
