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c++istream-iterator

Some bytes are missing after reading an std::ifstream to a vector of lines

For copying what I read from input file to vector, I used std::copy() as recommended in Reading an std::ifstream to a vector of lines.

The problem occurs if I use: 

std::copy(std::istream_iterator<unsigned char>(inputfile),
          std::istream_iterator<unsigned char>(),
          std::back_inserter(myVector));

The 16th byte of my file is missing in the myVector variable.

But if I use the following code:

inputfile.read((char*)&myVector[0], sizeof(int)*getfilesize(nameOfFile));

Then the byte is not missing anymore.

I am trying to parse WAV files and I lost too much time on this, I hope I will learn something new out of this. Can you please tell me what is wrong with the first version of the code above?

Solution

  • istream_iterator uses operator >> to read elements, but operator >> skip whitespaces.

    You may try using noskipws

    inputfile >> noskipws;

    § 24.6.1 p1. (my emphasis)

    The class template istream_iterator is an input iterator (24.2.3) that reads (using operator>>) successive elements from the input stream for which it was constructed....