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data conversion c++ string

I am getting data from a hardware API in the format below:

typedef struct _CRYPTOAPI_BLOB {
                                          DWORD cbData;
      __field_bcount(cbData) BYTE *pbData;
} DATA_BLOB, *PDATA_BLOB;

The data returned as I can see in the debug window has a valid non-zerovalue for
cbData. But pbData[0] invariably has '\0'. My first question is, is that valid as
I am getting binary data, possibly the first character is null and yet I have valid data
in the rest of the memory locations?

My second question is, assuming I have valid data, about converting this to a
string so I can pass this data to a socket. I plan to use a std::vector<char>.
but for now to use existing function that accepts a string argument what is a safe way of
converting?

method 1:

      PDATA_BLOB xxx; //returned with values
      std::string rawdata((char*)xxx->pbData, xxx->cbData);

currently I use this method and invaribaly the string rawdata is null ("").
not sure if it is bcoz I receive null data or if the conversion fails, and hence my
first question

method 2:

for (i = 0; i < xxx->cbData; i++) {
  string[i] = xxx->pbData[i];
}

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Infinity08

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SOLUTION

sarabande

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ol muser

ASKER

for some reason string didn't do it, vector<char> does the trick!

sarabande

i think the string problem is only a visual issue. whenever you look to a string with binary zeros with debugger you won't see the data. also the c_str member function would return an empty value because of the leading zero.

but vector<char> is more than an equivalent choice.

Sara