Using HDLC.FRAME Protocol

Status and Error Messages

Status and Error Messages

Error conditions and important events are reported to the application program through three kinds of status codes. These are “Transmit completion”, “Unsolicited” and “Receive completion” status codes.

The defines for these status codes are located in /usr/include/zcomstatus.h and /usr/include/zx25status.h.

Transmit Completion Status Codes

Transmit completion status is generated by the protocol on all transmit messages. Depending on the mode parameter selected when using the zsend call, the application will see either No transmit response messages, Error responses only, or All transmit response messages. The status code contained in the header of these messages indicates either the successful transmission of the message, or the reason why it could not be transmitted.

Chapter 3

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