SNAX/APN Application Programming Manual

Handling Errors in SNAX/APN Applications

SNAX/APN Application Programming Manual—420111-001

B-7

SNALU Outbound RU Error Codes

File-system error 182 indicates that SNAX/APN was unable to transmit an outbound RU

passed to it by a user’s PLU or SLU process. A PLU or SLU process always uses

WRITEREAD calls to send outgoing data and to receive incoming data. As discussed in

Section 4, The SNALU Interface

, a WRITEREAD call can be formatted to initiate:

•

A write operation

•

A read operation

•

A write operation followed by a read operation

If, after accepting a write operation, SNAX/APN cannot successfully transmit the BIU

to the specified destination LU, it notifies the user’s process. SNAX/APN completes the

next available read operation (via an outstanding AWAITIO call) with CCL and

FILEINFO error 182. This response corresponds to some previously issued write

portion of a WRITEREAD request.

When the application detects file error 182, it must correlate the sequence number

returned in the SNAX/APN header with the outbound request it was attempting to send.

When an AWAITIO call completes with CCL and FILEINFO error 182, the count-read

variable referenced by the associated WRITEREAD call is set to 9, indicating that the

associated I/O buffer contains only a SNAX/APN header. The detailed SNALU error

code is contained in the status area (two bytes) of the SNAX/APN header.

The third and fourth bytes of the header contain a SNALU error number specifying why

the RU could not be sent. The user’s error handling routine ascertains which RU could

not be sent by examining the sequence number field of the returned SNAX/APN header.

Outbound RU error codes can be grouped into the following categories:

•

Data integrity errors

•

SNA environment errors

•

SNA logical errors

The detailed codes that could be returned in the SNAX/APN header status area are listed

below by category.

Data Integrity Errors

Data integrity errors are returned when SNAX/APN detects a condition that prevents

completion of the request. Table B-3 lists the data integrity error codes.

Caution. If the application is sending data, the user’s PLU or SLU process should always have

a read operation outstanding to detect outbound RU errors.