C   reading from a file
ATOM      1  N   PRO     1     -38.396  -1.525   2.011 -0.18 14.01
ATOM      2  CA  PRO     1     -36.931  -1.372   2.090  0.08 13.02
ATOM      3  C   PRO     1     -36.353  -0.411   1.059  0.35 12.01
ATOM      4  O   PRO     1     -36.988  -0.061   0.086 -0.37 16.00
ATOM      5  CB  PRO     1     -36.368  -2.749   1.735  0.03 14.03
ATOM      6  CG  PRO     1     -37.417  -3.202   0.763  0.01 14.03
ATOM      7  CD  PRO     1     -38.692  -2.893   1.489  0.08 14.03

std::string c1, c3, c4;
int c2, c5;
double c6, c7, c8, c9, c10;

if (!(input_stream >> c1 >> c2 >> c3 >> c4 >> c5 >> c6 >> c7 >> c8 >> c9 >> c10))
{
    // error
}

for (std::string line; std::getline(file_stream, line); )
{
    std::string c1, c3, c4;
    int c2, c5;
    double c6, c7, c8, c9, c10;

    std::istringstream iss(line);

    iss >> c1;
    if (c1 == "ATOM")
    {
        if (!(iss >> c2 >> c3 >> c4 >> c5 >> c6 >> c7 >> c8 >> c9 >> c10))
        {
            // error
        }
    }
}