Fndownreq() - VeriFone MX800 series Programmer's Manual

V P
ISUAL AYMENTS

fnDownReq()

fnDownReq()
NOTE
262
M X 800 S P
ERIES ROGRAMMERS
Called after a REQ packet is received on the Down Channel. The application can:
•
allow or disallow this command to proceed
•
perform the request and detail the result.
If this callback function is not provided, all REQ commands will be allowed to run.
VP library will send the ACK prior to issuing this callback.
System mode may use this to put up downloading status.
Prototype
int fnDownReq(int iDownFd, int iFieldCount, vp_field_t *pszFields);
typedef struct
{
char key[MAX_KEY_SIZE];
char value[MAX_VALUE_SIZE];
} vp_field_t;
Parameters
Socket fd of Down Channel.
iDownFd
Number of fields in the array.
iFieldCount
Pointer to array of field structure.
pszFields
Return Values
> 0 Allow
0 Success, application performed the request
-1 Disallow, and don't ask again
-2 Disallow, terminal busy, try again
-3 Failure, application performed the request
-4 Failure
G
UIDE