gtpi1m3q | System Installation Support Reference |
The Mapping of Airline Traffic over Internet Protocol (MATIP) assign LNIATA
user exit, UMATAL, allows you to assign a line number, interchange address,
and terminal address (LNIATA) to a specific incoming data message. You
can also use this user exit to assign an LNIATA to a data message received by
the IP Bridge if you know the original Internet Protocol (IP) address.
UMATAL is called in CMADAT, CMOA, and CRII.
Input
- lniata
- A pointer to an unsigned integer that will contain the LNIATA on
return.
- session_type
- An unsigned integer containing the session type (Type-A conversational,
Type-A host-to-host, Type-A, Type B, or IP Bridge).
- IPaddress
- A pointer to the 4-byte IP address of the message origin.
- message_ID
- A pointer to the message identifier (ID). The contents of this
field depend on the session type indicator:
- If Type-A conversational, the agent set control unit (ASCU) identifier
(H1, H2, A1, A2 values from MATIP Session Open request) and terminal address
from the data packet.
- If Type-A host-to-host, the host identifier (H1, H2 values from the MATIP
Session Open) and flow ID from the data packet (if present).
- If Type B, the sender high-level designator (HLD) and recipient
HLD.
- If IP Bridge, the port number on which the message was received.
Programming Considerations
- You must be able to assign the appropriate LNIATA based on information
obtained from the original MATIP headers.
- All data levels must be returned to the caller in the same state that they
were on entry.
- The length of the message identifier field varies depending on the session
type:
- The Type-A conversational field is 5 bytes.
- The Type-A host-to-host field is 3 bytes.
- The Type B field is 4 bytes.
- The IP Bridge field is 2 bytes.
Return Values
UMATAL returns one of the following values:
- 0
- The LNIATA is identified and returned to the caller.
- Negative Number
- The LNIATA is not identified and, therefore, is not returned to the
caller.