DLREQUEST_TEST


Test the data link by sending a test command to the remote station and waiting for a test response. Application dependent test information is passed in buffer member of primitive structure. This is a confirmed service. Confirm will contain an echoed copy of the information field.

If a response is not received within the response timeout period, the command is resent. If the frame is resent the number of times specified by the retry limit without receiving a response, the request completes with DLFLAG_ERROR set in the DLCONFIRM_TEST primitive.

If DLFLAG_INLINE_ADDRESS is set in Flags, an HDLC address must be prepended to the data in Buffer and Size set to the number of bytes in the address and information field. This address overrides the addresses specified in the MGSL_DLPARAMS structure.

Flags can be 0 or a combination of the following flags:

DLFLAG_POLL Send command with Poll bit set and require response to have Final bit set. This option is usually set to help match the response to the command.
DLFLAG_BROADCAST Send command using broadcast address.
DLFLAG_INLINE_ADDRESS An HDLC address must be prepended to the data in Buffer and Size set to the number of bytes in the address and information field. This address overrides the addresses specified in the MGSL_DLPARAMS structure.

Type DLREQUEST_TEST
Flags As described above
Size Size in bytes of information field
Buffer Contains information field (test information)

MgslDlCall will return ERROR_INVALID_REQUEST if the specified link is a normal response mode secondary station. Secondary stations are not permitted to send commands.

Only one XID, TEST, or CFGR request may be active. Issuing another such request before the original completes results in a return code of ERROR_BUSY. Cancel an active request by issuing another request of the same kind with DLFLAG_CANCEL set in Flags, Size set to 0, and Buffer unused. A canceled request will not generate an accompanying confirmation primitive.


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