Building a program to do such a thing is using a power-jack hammer to
remove a screw.  You're using the wrong tool.

If you have Windows on the laptop, you might be able to use the Terminal
applet to transfer via a null modem cable.  I think Terminal had XMODEM
capability.

Otherwise, your only option is to write transmitter/receiver programs on
the two computers.  One to read the file on the sending computer and convert
the binary hex into ascii text and write it through the com port.  The other
on the receiving computer to take the ascii text coming through the com port,
convert each ascii hex character pair back into binary and write it to a
file.  I've done it.  It's a pain, but it works.

If you already have MS-DOS 6.22 and a NULL modem all that you need to do
is run INTERLNK.EXE on one computer and INTERSVR.SYS on the other.  This
will require you to tweak your CONFIG.SYS and AUTOEXEC.BAT files, but
the instructions are pretty obvious within the DOS HELP screens.

http://home.sprynet.com/sprynet/skotfred/

On the other
  OPEN "COM2:1200,N,8,1" FOR RANDOM AS #1
  OPEN "mode.com" for input as #2
  DO
     A$=INPUT$(2,1)
         PRINT #1, A$;
  LOOP UNTIL EOF(2)
  END

This should work - however, it is 1:38am.  The major screwup will
come if I forgot which input/output verbs go with which file modes.

I believe with binary it is GET$/PUT.  With every mode, print should
work.

However, if I did screwup the syntax, just look in the online help.
The basic (pun not intended) is that the receiving end opens the
port, waits for bytes to start arriving, writes them one-by-one to
the output file and quits when they stop.  The sender opens the file
and starts pumping out bytes until done and then quits.

'BY STEVEN SENSARN

DIM BYTE AS STRING * 1

CLS

'change this line to your settings
OPEN "COM2:9600,N,8,1,CD600,CS1,OP0" FOR RANDOM AS #1

DO
    'instead of reading the byte from the keyboard, read it from the file
    BYTE = INKEY$
    IF BYTE <> " " THEN
        'i don't know what the ascii code for an EOF is--change 27 to that
        IF BYTE = CHR$(27) THEN CLOSE : END
        'waits for thr empty in lsr (i think--i forget)
        'notice &H2F8--change this to the base port address of your modem:
        'COM1:3F8h
        'COM2:2F8h
        'COM3:3E8h\may have gotten these mixed up--but your not using them
        'COM4:2E8h/anyways
        WAIT (&H2F8 + 5), 32
        'send byte across port
        'change this &h2F8 too
        OUT &H2F8, ASC(BYTE)
    END IF
        'if char in rbr then it is read
        'change this &h2F8 too
    IF (INP(&H2F8 + 5) AND 1) = 1 THEN
        'read byte
        'change this &h2f8 too
        BYTE = CHR$(INP(&H2F8))
        'instead of sending the byte to the screen, save it to the file
        PRINT BYTE;
    END IF
LOOP

Even after changing that program, I'm not sure if it would work due to the
EOF thing (I haven't done much file transfer stuff).

Steven Sensarn

______________________________

Have a look for a program called  "FX"  this is a simple file transfer
and remote access program.

 As long as you can access the remote port, the program allows you to
"upload" the .exe file to the remote machine.

 I have used this program many times to get out of a "transfer jam"

 Need more details ?

 email me.

 Regards,
         Glenville T. Sawyer

that shows STEP-BY-STEP how to make a Parallel-port adapter using the

Radio-Shack 25-Male to 25-Female junction-box designed exactly for the

"FX" program.  ...also works with the "LAP-LINK" software.

so "RING" me-E if anyone is interested.

Beau Schwabe