NAME

std::basic_stringbuf::setbuf - std::basic_stringbuf::setbuf

Synopsis

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

If s is a null pointer and n is zero, this function has no effect.

Otherwise, the effect is implementation-defined: some implementations do nothing,
while some implementations clear the std::string member currently used as the buffer
and begin using the user-supplied character array of size n, whose first element is
pointed to by s, as the buffer and the input/output character sequence.

This function is protected virtual, it may only be called through pubsetbuf() or
from member functions of a user-defined class derived from std::basic_stringbuf.

Parameters

s - pointer to the first CharT in the user-provided buffer or null
n - the number of CharT elements in the user-provided buffer or zero

Return value

this.

Notes

The deprecated stream buffer std::strstreambuf or the boost.IOStreams device
boost::basic_array may be used to implement I/O buffering over a user-provided char
array in portable manner.

Example

Test for the stringstream's setbuf functionality

// Run this code

#include <iostream>
#include <sstream>

int main()
{
std::ostringstream ss;
char c[1024] = {};
ss.rdbuf()->pubsetbuf(c, 1024);
ss << 3.14 << '\n';
std::cout << c << '\n';
}

Output:

3.14 (on GNU g++/libstdc++ and SunPro C++/roguewave)
<nothing> (on MS Visual Studio 2010, SunPro C++/stlport4, CLang++/libc++)