question about private key of BTS

[BTSdac]

Those 8 bytes are a pointer to the private key which is 32 bytes.

thanks 

[bytemaster]

Those 8 bytes are a pointer to the private key which is 32 bytes.

[BTSdac]

I read bts code recently ,but I am a newbee of code . so many question about it
I notice private class
just use this union to record private key ?
    union {
      T    _align;
      char _data;
}