You can choose to create the write-operation-blocks for the WRITE_DATALIST request in the storage area referenced either by BUFFER or BUFLIST. Each buffer area must be 4096 bytes long. BUFFER defines an area containing an array of from 1 to 256 WOBs, followed by the corresponding data areas to be written to each entry specified in the WOBs. The buffer area must be addressable in the caller's primary address space or from the caller's PASN access list.

BUFLIST defines a set of buffers that will contain an array of from 1 to 16 WOBs, followed by the corresponding data areas to be written to each entry specified in the WOBs. WOBs can only be specified in the first buffer pointed to by the first BUFLIST entry. That first buffer must reside in 31-bit virtual storage. All other buffers pointed to by BUFLIST entries may reside in 31-bit or 64-bit virtual storage. Real storage addresses cannot be used.