This form posts a transaction, and the server response comes straight back to the browser window as a newline-delimited string.
How do I capture the server response?
The form button: https://www.calligraphydallas.com/stuff/AGI-newline.html
The form code (just save as html, launch it and submit it to see the behavior)
<html>
<form method='Post' action= 'https://www.paymentsgateway.net/cgi-bin/posttest.pl'>
<input type='hidden' name='pg_merchant_id' value='191620'/>
<input type='hidden' name='pg_password' value='PASSWORD02'/>
<input type='hidden' name='pg_transaction_type' value='10'/>
<input type='hidden' name='pg_total_amount' value='11.11'/>
<input type='hidden' name='ecom_payment_card_type' value='visa'/>
<input type='hidden' name='ecom_payment_card_name' value='James D Ivey'/>
<input type='hidden' name='ecom_payment_card_number' value='4111111111111111'/>
<input type='hidden' name='ecom_payment_card_expdate_month' value='08'/>
<input type='hidden' name='ecom_payment_card_expdate_year' value='2020'/>
<input type='hidden' name='ecom_payment_card_verification' value='123'/>
<input type='hidden' name='ecom_billto_postal_name_first' value='Forte'/>
<input type='hidden' name='ecom_billto_postal_name_last' value='Test'/>
<input type='hidden' name='ecom_billto_postal_street_line1' value='500 W Bethany Dr'/>
<input type='hidden' name='ecom_billto_postal_street_line2' value='Suite 200'/>
<input type='hidden' name='ecom_billto_postal_city' value='Allen'/>
<input type='hidden' name='ecom_billto_postal_stateprov' value='TX'/>
<input type='hidden' name='ecom_billto_postal_postalcode' value='75013'/>
<input type='submit' value='Pay Now'/>
</form>
</html>