Because shift-out and shift-in characters do not occupy positions on a printer, ISPF inserts a blank character before each shift-out and after each shift-in.
Field-outlining information is embedded in the record as a set-attribute (SA) order. Each SA order occupies three bytes. One SA is required to start field-outlining, one to end field-outlining, and one to change field-outlining. Therefore, each affected field normally takes six additional bytes.