On Alpha and Integrity server systems, changes the access mode of
    the calling process to kernel mode. This service allows a process
    to change its access mode to kernel, execute a specified routine,
    and then return to the access mode in effect before the call was
    issued.
    This service accepts 64-bit addresses.
    Format
      SYS$CMKRNL_64  routin_64 ,arglst_64
    C Prototype
      int sys$cmkrnl_64  (int (*routin_64)(__unknown_params),
                         unsigned __int64 *arglst_64);
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