On Alpha and Integrity server systems, changes the access mode of
    the calling process to executive mode.

    This service accepts 64-bit addresses.

    Format

      SYS$CMEXEC_64  routin_64 ,arglst_64

    C Prototype

      int sys$cmexec_64  (int (*routin_64)(__unknown_params),

                         unsigned __int64 *arglst_64);