__sysc_pad
__sysc_pad(struct sysctlnode*) _suc_child; /* array of child nodes */
__sysc_pad(void*) _sud_data; /* pointer to external data */
__sysc_pad(size_t) _sud_offset; /* offset to data */
__sysc_pad(size_t) _sysctl_size; /* size of instrumented data */
__sysc_pad(sysctlfn) _sysctl_func; /* access helper function */
__sysc_pad(struct sysctlnode*) _sysctl_parent; /* parent of this node */
__sysc_pad(const char *) _sysctl_desc; /* description of node */