A DDCM3 logical terminal exchanges messages with another logical terminal. When a DCCM3 logical terminal communicates with a CUP of TP1/Client, the DCCM3 logical terminal uses the IP address and the DCCM3 logical terminal's port number to identify the CUP as a logical terminal.

When a DCCM3 logical terminal communicates with a multi-thread CPU, a service request from any thread has the same IP address and port number. Therefore, if several DCCM3 logical terminals that communicate with a multi-thread CUP are defined on the DCCM3 side, the combination of the CUP and the DCCM3 logical terminal is not unique. This may cause problems to some applications since the sequence of DCCM3 server processing is not guaranteed when different DCCM3 logical terminals receive service requests.

When you use a permanent connection to communicate with a DCCM3 logical terminal, you can report the terminal identification information that you specify on TP1/Client to the DCCM3 logical terminal. Therefore, you can use the DCCM3's function for allocating a fixed terminal. Use the logical terminal name of the DCCM3 logical terminal as the terminal identification information.

By reporting the terminal identification information to the DCCM3 logical terminal, the CUP is always allocated to the same logical terminal. Therefore, you can identify the combination of the CUP and the logical terminal.

To report the terminal identification information to the DCCM3 logical terminal, specify the terminal identification information in DCCLTCONNECTINF of the client environment definition. Alternatively, execute the dc_clt_set_connect_inf_s function to set the terminal identification information.

When you use a permanent connection to communicate with the DCCM3 logical terminal, the following two methods are available. However, only method 2 can report terminal identification information to the DCCM3 logical terminal.

1. Specify the host name of the DCCM3 logical terminal in the DCCLTDCCMHOST client environment definition and the port number of the DCCM3 logical terminal in DCCLTDCCMPORT. Specify DCCLT_DCCM3 in the flags argument of the dc_clt_connect_s function.
2. Specify the host name and the port number of the DCCM3 logical terminal in the DCCLTRAPHOST client environment definition and specify DCNOFLAGS in the flags argument of the dc_clt_connect_s function.

• Reporting terminal identification information enables you to use DCCM3's function for allocating a fixed terminal only when you use DCCM3 version 09-03 and later. For details about the function for allocating a fixed terminal, see the manual VOS3 Data Management System XDM E2 Description.
• If DCCM3 does not define the logical terminal name of the DCCM3 logical terminal that matches the terminal identification information specified on TP1/Client, the dc_clt_connect_s function returns a DCCLTER_NET_DOWN error.