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)