CHECK macroinstruction

Must be issued in an addressing mode consistent with the addressing mode of the application program at the time the original request was made. For example, if an asynchronous RECEIVE with EXIT=RECVEXIT was issued in 24-bit addressing mode, the code in procedure RECVEXIT must be in 24-bit addressable storage. Issuing the CHECK macroinstruction in 24-bit addressing mode for a request that was issued in 31-bit addressing mode can have unpredictable results. In addition, all control blocks used by the CHECK macroinstruction must reside in storage consistent with the application program's addressing mode.