Pathway/iTS Management Programming Manual

SPI Programming Considerations
NonStop Pathway/iTS Management Programming Manual—426749-002
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Event and Error Handling
structured token, you must first obtain the entire structured token by using SSGET.
Then refer to the fields of the structure by using the defined field names.
The PATHMON process does not provide support for selecting the types of responses
to be returned with the SPI standard token ZSPI-TKN-RESPONSE-TYPE. The
Pathway subsystem always returns a response for every object—whether or not errors
or warnings occur for the object. For more information on sending messages and
receiving the responses, see the SPI Programming Manual.
Event and Error Handling
Each response returned by the Pathway subsystem includes a return token (ZSPI-
TKN-RETCODE), whose value indicates whether an error occurred when the
PATHMON process attempted to perform the command. An error is a serious condition
that prevents the command from being completed. If the command completes with no
errors, the value of the return token is zero. If ZSPI-TKN-RETCODE has any nonzero
value, this means that an error occurred. In this case, the PATHMON process includes
an error list in the response, providing information about the error.
A warning reports a condition less serious than that of an error. If no errors occur but a
warning occurs, the return token has a value of zero, but an error list appears in the
response, providing information about the warning condition.
An error list, which always begins with the token ZSPI-TKN-ERRLIST and ends with
the token ZSPI-TKN-ENDLIST, is returned only if an error or warning is detected. The
information in the list becomes accessible when your program calls SSGET to select
ZSPI-TKN-ERRLIST. Although the Pathway subsystem only returns one error list per
response, there can be nested error messages.
The PATHMON process does not support ZSPI-TKN-ALLOW-TYPE. The SPI standard
token ZSPI-TKN-RETCODE contains a nonzero value if the PATHMON process
detects an error in a command message or detects an error when attempting to
perform a command. The Pathway subsystem can also return file-system errors.
Event Message Subject Tokens
ZEMS-TKN-SUBJECT-MARK indicates the subject token, which identifies the Pathway
subsystem object or file that is most directly involved in the event. The subject token
indicates one of the tokens listed in Table 3-7 as present in the event-message buffer:
Table 3-7. Event Message Subject Tokens
Token Description
ZPWY-TKN-FNAME Event concerns a file.
ZPWY-TKN-PMNAME Event concerns the PATHMON process.
ZPWY-TKN-PROGNAME Event concerns a terminal template (PROG object).
ZPWY-TKN-TCPNAME Event concerns a terminal control process (TCP).