Determining negotiated values

The application program on the source and target side of the CNOS negotiation can determine the existing session limit values that have been negotiated. The methods for doing this are shown in Table 1.

Table 1. Methods for determining negotiated values
LU	Method	Description
Source side only	Checks the CNOS session limits control block	If the application program specified a CNOS session limits control block as input to the CNOS macroinstruction, VTAM® writes the negotiated values back to the CNOS session limits control block when completing the CNOS negotiation. The application program can read the new values directly from the CNOS session limits control block.
Target side only	Processes the ATTN(CNOS) exit	When a CNOS negotiation completes successfully, VTAM schedules the LU's ATTN exit if the application program has one. The ATTN exit is scheduled with the results of the CNOS negotiation, which the application program can read. For more information on the ATTN exit, see Using the ATTN exit. Note: If a CNOS negotiation is processed as a result of the MODIFY CNOS command or an automatic internal CNOS, VTAM schedules the ATTN exit for both the source and target side.
Source or target side	Issues the DISPLAY macroinstruction	The application program can issue an APPCCMD CONTROL=OPRCNTL, QUALIFY=DISPLAY macroinstruction to retrieve from the LU-mode table current information about the partner LU and the logon mode.