IIUG Software Repository Files

CREDIT CARD VERIFICATION PROGRAM

This is a short description of how I developped a program to use the
commercial ICVERIFY program to interface to INFORMIX-4GL or R4GL.

I also have the same interface to ISQL.

The ICVERIFY program looks at the data  directory and scans for files that end
with ".REQ".  It picks up the request and dials the creditcard service with a
modem and then gets an answer for the transaction which was posted in the .REQ
file.

When it has picked up the file it moves it to .HLD and when it has received the
answer it moves it to .ANS.  This process usually takes 13 to 23 seconds.  The
user gets a small display at the bottom of the screen that scrolls every 5
seconds to let him know that it is being processed.

My C program creates the .REQ file using parameters from the CALL in
Informix-4GL.  It then watches the directory where the file was put and scans
for the .HLD and the .ANS files.  When the .ANS file is there it picks it up
and uses the data returned from the creditcard service and fills in the
appropriate fields on the screen and saves the form.  I have built some
safegards for refused or cancelled creditcard authorizations but there may be
more messages from the creditcard company that I don't know about.

To use this you must create a .4ge program that includes call to the C-program
or create a new 4glgo engine to use it with R4GL.  I included the programs to
generate the new 4glgo that I called sell and selldbug.

The C program is called credit.ec.
You also need to use fgisell.c
The script to create the sell engine is called mksell.
I included the source for chk_cre.4gl so you can debug your program.
I included the 4gl source code for the simple call to credit_chk() in
  psc_cshr1.4gl.  This program is just a module part of a large set
  of modules.  You can use the example of the call to credit_chk(...) as
  a start for your application.
I also included the form that goes with this 4gl module psc_cshr1.per.

You can contact IC-SYSTEMS at 283 Beau Forest Dr.
                             Oakland CA 94611
                             (510) 339-3480.

ICVERIFY is not cheap but the return in time saved pays the program in no time.


Good luck to all of you.

    Guy St-Amant
    gstamant@aol.com
    (305) 779-7803
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