To create a buffer on the data stack before adding more elements to the stack, use the TSO/E REXX MAKEBUF command. All elements added to the data stack after the MAKEBUF command are placed in the buffer. Below the buffer are elements placed on the stack before the MAKEBUF command.

Instructions that could be used to create the illustrated buffer are as follows:

'MAKEBUF'
PUSH 'newX'
QUEUE 'newY'