Final register contents

The routine must leave the register status as follows:

Register 0:: Minimum VR window size (if register 15=0)
Note: This value must be greater than zero and less than or equal to the maximum value specified in register 1.
Register 1:: Maximum VR window size (if register 15=0)
Note: This value must be greater than or equal to the minimum value specified in register 0 and less than or equal to 255.
Registers 2–14:: Restored to entry contents
Register 15:: Return code of 0 if the minimum and maximum window size values are to be used by VTAM®. Any nonzero return code (or values that are not valid specified in register 0 or 1) causes VTAM to ignore the values indicated by registers 0 and 1. Instead, it uses a minimum window size equal to the ER length and a maximum window size of three times the ER length, or the minimum and maximum window sizes that you defined on the PATH definition statement, if any.

For more information about specifying virtual route pacing window sizes on the PATH definition statement, see z/OS Communications Server: SNA Resource Definition Reference.