Extension of the CMS IUCV Interface of VM/SP
Original Publication Date: 1987-Aug-01
Included in the Prior Art Database: 2005-Feb-01
This article proposes an extension of the CMS IUCV interface available in VM/SP, for solving the following problem: The first eight bytes of the user data field in IUCV CONNECT are reserved for exclusive use by CMS IUCV; other applications which would also need this field cannot use it. When several independent programs need to use IUCV in a virtual machine VM1, a demultiplexing program is required to forward the IUCV interrupts to the appropriate program. CMS IUCV has been introduced in VM/SP for that purpose (cf. VM/SP System Programmer's Guide; IBM ordering No. SC19-6203). Each program in VM1 using IUCV can register to this demultiplexing program under a unique name. CMS IUCV monopolizes the first 8 bytes of the user-data field in IUCV CONNECT.