std::stringbuf::stringbuf

(1) empty constructor (default constructor)

Constructs a stringbuf object with an empty sequence as content, and argument which as open mode.

(2) initialization constructor

Constructs a stringbuf object with a copy of str as content, and argument which as open mode.

(3) copy constructor (deleted)

Deleted (no copy constructor).

(4) move constructor

Acquires the contents of x.
x is left in an unspecified but valid state.
It is unspecified whether the internal sequence is the one in x before the call, or a copy of it. In any case, both objects use independent sequences after the call.

Parameters

str

A string object, whose content is copied.

x

A stringbuf object, whose value is moved.

which

Open mode: Access given to the internal sequence of characters through the internal pointers that define the stream buffer's input sequence and output sequence. It is an object of type ios_base::openmode for which any combination of the following constant values is significant:

value	stands for	access
ios_base::in	input	The sequence can be read: Members eback, gptr and egptr are maintained with values pointing to elements of the internal character sequence.
ios_base::out	output	The sequence can be written: Members pbase, pptr and epptr are maintained with values pointing to elements of the internal character sequence.

Other values of type ios_base::openmode may also be specified, although whether they have an effect on stringbuf objects depends on the library implementation.

value	stands for	access
ios_base::in	input	The sequence can be read: Members eback, gptr and egptr are maintained with values pointing to elements of the internal character sequence.
ios_base::out	output	The sequence can be written: Members pbase, pptr and epptr are maintained with values pointing to elements of the internal character sequence.
ios_base::ate	at end	The put pointer (pptr) starts at the end of the sequence, and is reset to that position every time the contents are changed using member str.

Other values of type ios_base::openmode (such as ios_base::app) may also be specified, although whether they have an effect on stringbuf objects depends on the library implementation.

Example

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// stringbuf example
#include <iostream>     // std::cout, std::ostream, std::hex
#include <sstream>      // std::stringbuf
#include <string>       // std::string

int main ()
{
  std::stringbuf buffer;      // empty stringbuf

  std::ostream os (&buffer);  // associate stream buffer to stream

  // mixing output to buffer with inserting to associated stream:
  buffer.sputn ("255 in hexadecimal: ",20);
  os << std::hex << 255;

  std::cout << buffer.str();

  return 0;
}

255 in hexadecimal: ff

Data races

Exception safety

See also

stringbuf::str

Get/set the string content (public member function)