std::basic_ios::rdbuf
From cppreference.com
std::basic_streambuf<CharT, Traits>* rdbuf() const; |
(1) | |
std::basic_streambuf<CharT, Traits>* rdbuf( std::basic_streambuf<CharT, Traits>* sb ); |
(2) | |
Manages the associated stream buffer.
1) Returns the associated stream buffer. If there is no associated stream buffer, returns a null pointer.
2) Sets the associated stream buffer to
sb
. The error state is cleared by calling clear(). Returns the associated stream buffer before the operation. If there is no associated stream buffer, returns a null pointer.Parameters
sb | - | stream buffer to associate to |
Return value
The associated stream buffer, or a null pointer if there was no associated stream buffer.
Exceptions
(none)
Example
Run this code
#include <iostream> #include <sstream> int main() { std::ostringstream local; auto cout_buff = std::cout.rdbuf(); // save pointer to std::cout buffer std::cout.rdbuf(local.rdbuf()); // substitute internal std::cout buffer with // buffer of 'local' object // now std::cout work with 'local' buffer // you don't see this message std::cout << "some message"; // go back to old buffer std::cout.rdbuf(cout_buff); // you will see this message std::cout << "back to default buffer\n"; // print 'local' content std::cout << "local content: " << local.str() << "\n"; }
Output:
back to default buffer local content: some message
See also
replaces the rdbuf without clearing its error state (protected member function) |