std::basic_streambuf::pubsetbuf, std::basic_streambuf::setbuf

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basic_streambuf<CharT, Traits>* pubsetbuf( char_type* s, std::streamsize n )	(1)

protected: virtual basic_streambuf<CharT, Traits>* setbuf( char_type* s, std::streamsize n )	(2)

1) Calls setbuf(s, n) of the most derived class

2) The base class version of this function has no effect. The derived classes may override this function to allow removal or replacement of the controlled character sequence (the buffer) with a user-provided array, or for any other implementation-specific purpose.

#include <fstream>
#include <iostream>
#include <string>
 
int main()
{
    int cnt = 0;
    std::ifstream file;
    char buf[10241];
 
    file.rdbuf()->pubsetbuf(buf, sizeof buf);
 
    file.open("/usr/share/dict/words");
 
    for (std::string line; getline(file, line);) {
        cnt++;
    }
 
    std::cout << cnt << '\n';
}

[edit] See also


setbuf [virtual]	provides user-supplied buffer or turns this filebuf unbuffered (virtual protected member function of `std::basic_filebuf`)

Language
Standard library headers
Concepts
Utilities library
Strings library
Containers library
Algorithms library
Iterators library
Numerics library
Input/output library
Localizations library
Regular expressions library (C++11)
Atomic operations library (C++11)
Thread support library (C++11)

std::basic_streambuf::pubsetbuf, std::basic_streambuf::setbuf

Contents

[edit] Parameters

[edit] Return value

[edit] Example

[edit] See also

s	-	pointer to the first byte in the user-provided buffer
n	-	the number of bytes in the user-provided buffer