I would like to pack() the equivalent of a Microsoft DATA_BLOB structure, which looks like this:
typedef struct DATA_BLOB {
  DWORD cbData; // DWORD that contains the count, in bytes, of data.
  BYTE *pbData; // Pointer to the data buffer.
}

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According to MSDN, a DWORD is a 32-bit unsigned long. So, in terms of pack(), I assume a DWORD corresponds to 'L'. The second member of the structure, a BYTE pointer to the data, seems a little more tricky. Since it needs a pointer to the data, I assume pack() is going to expect 'P', but I think a BYTE is 'C', so maybe some double packing is required? Here's what I've come up with...how far off am I?

my $data_blob = pack('LC', length($data), pack('P', $data));

In reply to pack() Question - DATA_BLOB structure by PerlRob

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