#g4ppinv_updateInvoice

 *//////////////////////////////////////////////////////////////*

 * #g4ppinv_updateInvoice - Update an Invoice                   *

 *                                                              *

 * Input                                                        *

 *   in_invID - The ID of the invoice to update.                *

 *                                                              *

 * Input/Output                                                 *

 *   in_out_invFile - The fully qualified path and name of the  *

 *    JSON file that contains the invoice information as        *

 *    generated by PayPal.                                      *

 *    If this value is blank the filename and path will be      *

 *    automatically generated.                                  *

 *    NOTE: This file will only exist is the value for          *

 *    save_invoice_draft is set to true.                        *

 *                                                              *

 * Output:                                                      *

 *   out_errMsg - The error message (if error exists).          *

 *                                                              *

 * Returns:                                                     *

 *   -1 for error, 0 for no error.                              *

 *                                                              *

 * Settable Variables ([r]=required)                            *

 *   account - PayPal Account ID [r]                            *

 *   All remaining values are the same as                       *

 *     g4ppinv_createInvoice() except number which is passed    *

 *     in as a parameter.                                       *

 *                                                              *

 *//////////////////////////////////////////////////////////////*

D #g4ppinv_updateInvoice...

D                 PR            10i 0

D  in_invID                    256

D  in_out_invFile...

D                              256

D  out_errMsg                  256    Options(*NOPASS)