| 1 | Receiver variable | Output | Char(*) |
| 2 | Length of receiver variable | Input | Binary(4) |
| 3 | Format name of receiver variable | Input | Char(8) |
| 4 | Request variable | Input | Char(*) |
| 5 | Length of request variable | Input | Binary(4) |
| 6 | Format name of request variable | Input | Char(8) |
| 7 | Error code | I/O | Char(*) |
The Wait Message (QzdmWaitMessage) API is used to wait for a message on an OptiConnect stream. The message may be a request message, a response message, or a control message.
The following restrictions apply:
The receiver variable that is to receive the output control information from the Wait Message (QzdmWaitMessage) API.
The length of the receiver variable, in bytes. The length of the receiver variable must be at least equal to or greater than the length of the output format.
The format of the information that is returned from the Wait Message (QzdmWaitMessage) API. The WMRC0100 format is used by this API for the receiver variable. See WMRC0100 Format for more information on the WMRC0100 format.
The request variable structure that describes the input for the Wait Message (QzdmWaitMessage) API.
The length of the request variable, in bytes. The length of the request variable must be at least equal to the length of the input format, and less than or equal to the maximum length of 4KB.
The format of the information that is provided as input for the Wait Message (QzdmWaitMessage) API. The WMRQ0100 format is used by this API for the request variable. See WMRQ0100 Format for more information on the WMRQ0100 format.
The structure in which to return error information. For the format of the structure, see Error code parameter.
The following table defines the information returned for Format WMRC0100.
| Offset | Type | Field | |
|---|---|---|---|
| Dec | Hex | ||
| 0 | 0 | CHAR(1) | Message type |
The following table defines the information required for Format WMRQ0100.
| Offset | Type | Field | |
|---|---|---|---|
| Dec | Hex | ||
| 0 | 0 | CHAR(16) | Stream identifier |
| 16 | 10 | BINARY(4) | Time-out value |
Message type. The type of message that is received. This field is provided as output on the Wait Message (QzdmWaitMessage) API.
Possible values follow:
| 1 | Request message |
| 2 | Response message |
| 3 | Control message |
Stream identifier. The OptiConnect stream that is used for communications. This field is provided as output on the Open Stream (QzdmOpenStream) API.
Time-out value. A length of time, in milliseconds, to wait for the Wait Message (QzdmWaitMessage) API to complete. If the Wait Message (QzdmWaitMessage) API does not complete before the specified time-out value, the exception CPFADFE is returned. The user should then re-issue the Wait Message (QzdmWaitMessage) API and specify the same time-out value or an increased time-out value.
The Wait Message (QzdmWaitMessage) API remains outstanding, and control is not returned to the user application until either of the following occurs:
A value of -1 may be specified, which indicates to wait forever for the Wait Message (QzdmWaitMessage) API to complete.
| Message ID | Error Message Text |
|---|---|
| CPF24B4 E | Severe error while addressing parameter list. |
| CPF3C1D E | Length specified in parameter &1 not valid. |
| CPF3C21 E | Format name &1 is not valid. |
| CPF3C90 E | Literal value cannot be changed. |
| CPF3CF1 E | Error code parameter not valid. |
| CPF9872 E | Program or service program &1 in library &2 ended. Reason code &3. |
| CPFADF0 E | The OptiConnect QSOC subsystem must be active. |
| CPFADF1 E | OptiConnect communication error. |
| CPFADF5 E | OptiConnect API internal error, function code &1, return code &2. |
| CPFADF6 E | Request variable not valid, reason code &1. |
| CPFADFE E | Time-out occurred. |