std::strstreambuf::overflow

Appends the character c to the put area of the buffer, reallocating if possible.

# Declarations

protected:
virtual int_type overflow( int_type c = EOF );

(deprecated in C++98) (removed in C++26)

# Parameters

c: the character to store in the put area

# Return value

If c == EOF, returns some value other than EOF. Otherwise, returns (unsigned char)(c) on success, EOF on failure.

# Example

#include <iostream>
#include <strstream>
 
struct mybuf : std::strstreambuf
{
    int_type overflow(int_type c) 
    {
        std::cout << "Before overflow(): size of the put area is " << epptr()-pbase()
                  << " with " << epptr()-pptr() << " write positions available\n";
        int_type rc = std::strstreambuf::overflow(c);
        std::cout << "After overflow(): size of the put area is " << epptr()-pbase()
                  << " with " << epptr()-pptr() << " write positions available\n";
        return rc;
    }
};
 
int main()
{
    mybuf sbuf; // read-write dynamic strstreambuf
    std::iostream stream(&sbuf);
 
    stream << "Sufficiently long string to overflow the initial allocation, at least "
           << " on some systems.";
}