public member function
<fstream>

std::basic_ifstream::rdbuf

basic_filebuf<char_type,traits_type>* rdbuf() const;
Get stream buffer
Returns a pointer to the internal basic_filebuf object.

Notice however, that this is not necessarily the same as the currently associated stream buffer (returned by basic_ios::rdbuf).

Parameters

none

Return Value

A pointer to the internal basic_filebuf object.
char_type and traits_type are member types defined as aliases of the class template parameters (see basic_ifstream types).

Example

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// read file data using associated buffer's members
#include <iostream>     // std::cout
#include <fstream>      // std::filebuf, std::ifstream

int main () {
  std::ifstream ifs ("test.txt", std::ifstream::binary);

  // get pointer to associated buffer object
  std::filebuf* pbuf = ifs.rdbuf();

  // get file size using buffer's members
  std::size_t size = pbuf->pubseekoff (0,ifs.end,ifs.in);
  pbuf->pubseekpos (0,ifs.in);

  // allocate memory to contain file data
  char* buffer=new char[size];

  // get file data
  pbuf->sgetn (buffer,size);

  ifs.close();

  // write content to stdout
  std::cout.write (buffer,size);

  delete[] buffer;

  return 0;
}

Data races

Accesses the stream object.
Concurrent access to the same stream object may cause data races.

Exception safety

Strong guarantee: if an exception is thrown, there are no changes in the stream buffer.

See also