Gateway path selection function (function code X'04')

Use the gateway path selection function to shorten or reorder the list of gateway paths determined by GWPATH definition statements. (See z/OS Communications Server: SNA Resource Definition Reference for an explanation of the GWPATH statement.) If this function is not selected during the begin function processing, VTAM® selects the gateway NCP from the GWPATH statements defined for the selected SSCP.

Table 1 shows the parameter list pointed to by register 1. The parameters are described in Parameter descriptions.

Table 1. Gateway path selection function parameter list
Dec (Hex) Offset	Size (Bytes)	Description
0 (0)	4	Address of environment vectors
4 (4)	4	Address of function code and related session information
8 (8)	4	Address of user data field
12 (C)	4	Address of PLU resource identifier control vector
16 (10)	4	Address of SLU resource identifier control vector
20 (14)	4	Address of session ID
24 (18)	4	Reserved
28 (1C)	4	Address of gateway path selection list
68 (44)	4	Address of session authorization data vector
72 (48)	4	Address of VTAM exit services parameter list
76 (4C)	4	Address of session management data area