读取二进制文件

Question

I got segmentation problem while reading binary file.

File size is 16859136 bytes, containing double values, but in fact I can read about 4214784 bytes (4 times less).

I use the following c++ code.

const int size = 6*28*28*28*4*4; // 16859136(bytes) = size * 8(bytes)  
double data[size];

ifstream in;
in.open("/path/to/file", std::fstream::binary);
if (in.is_open()) { cout << "File is open!\n"; }

in.read((char *) &data, sizeof(data));
cout << in.gcount() << " bytes read\n";

in.close();

Output:

Segmentation fault

PS: Maybe there is some kind of syntax error...

Answer 1

The following lines allocate a space too large on your stack:

const int size = 6*28*28*28*4*4; // 16859136(bytes) = size * 8(bytes)  
double data[size];

consider instead a heap allocation:

std::vector<double> data(6*28*28*28*4*4);