From cppreference.com
template<classCharT,classTraits=std::char_traits<CharT>,classAllocator=std::allocator<CharT>>classbasic_stringbuf:publicstd::basic_streambuf<CharT,Traits>std::basic_stringbuf is a
whose associated character sequence is a memory-resident sequence of arbitrary characters, which can be initialized from or made available as an instance of
.
Typical implementations of std::basic_stringbuf hold an object of type
or equivalent resizable sequence container directly as a data member and use it as both the controlled character sequence (the array where the six pointers of
are pointing to) and as the associated character sequence (the source of characters for all input operations and the target for the output).
In addition, a typical implementation holds a data member of type
to indicate the I/O mode of the associated stream (input-only, output-only, input/output, at-end, etc).
If over-allocation strategy is used by
, an additional high-watermark pointer may be stored to track the last initialized character.
(since C++11)Several typedefs for common character types are provided:
Type Definition std::stringbufstd::basic_stringbuf<char>std::wstringbufstd::basic_stringbuf<wchar_t>Member types
Member type Definition char_typeCharT
traits_typeTraits; the program is ill-formed if Traits::char_type is not CharT.
int_typeTraits::int_type
pos_typeTraits::pos_type
off_typeTraits::off_type
allocator_typeAllocator
Exposition-only members
bufthe std::basic_string<CharT,Traits,Allocator> used as the underlying buffer
(exposition-only member object*)modethe
of the associated stream
(exposition-only member object*)initializes the input and output sequences
(exposition-only member function*)Public member functions
constructs a basic_stringbuf object
(public member function)
(C++11)
assigns a basic_stringbuf object
(public member function)
(C++11)
swaps two basic_stringbuf objects
(public member function)
(destructor)
[virtual](implicitly declared)
destructs a basic_stringbuf object and the string it holds
(virtual public member function)
replaces or obtains a copy of the associated character string
(public member function)
(C++20)
obtains a copy of the allocator associated with the internal sequence container
(public member function)
(C++20)
obtains a view over the underlying character sequence
(public member function)
Protected member functions
[virtual]
returns the next character available in the input sequence
(virtual protected member function)
[virtual]
puts a character back into the input sequence
(virtual protected member function)
[virtual]
appends a character to the output sequence
(virtual protected member function)
[virtual]
attempts to replace the controlled character sequence with an array
(virtual protected member function)
[virtual]
repositions the next pointer in the input sequence, output sequence, or both, using relative addressing
(virtual protected member function)
[virtual]
repositions the next pointer in the input sequence, output sequence, or both using absolute addressing
(virtual protected member function)
Non-member functions
Inherited from
Member types
Member type Definition char_typeCharT
traits_typeTraits; the program is ill-formed if Traits::char_type is not CharT.
int_typeTraits::int_type
pos_typeTraits::pos_type
off_typeTraits::off_type
Member functions
[virtual]
destructs the basic_streambuf object
(virtual public member function of std::basic_streambuf<CharT,Traits>)
Locales
changes the associated locale and invokes imbue()
(public member function of std::basic_streambuf<CharT,Traits>)
obtains a copy of the associated locale
(public member function of std::basic_streambuf<CharT,Traits>)
Positioning
invokes setbuf()
(public member function of std::basic_streambuf<CharT,Traits>)
invokes seekoff()
(public member function of std::basic_streambuf<CharT,Traits>)
invokes seekpos()
(public member function of std::basic_streambuf<CharT,Traits>)
invokes sync()
(public member function of std::basic_streambuf<CharT,Traits>)
Get area
obtains the number of characters immediately available in the get area
(public member function of std::basic_streambuf<CharT,Traits>)
advances the input sequence, then reads one character without advancing again
(public member function of std::basic_streambuf<CharT,Traits>)
(removed in C++17)
reads one character from the input sequence and advances the sequence
(public member function of std::basic_streambuf<CharT,Traits>)
reads one character from the input sequence without advancing the sequence
(public member function of std::basic_streambuf<CharT,Traits>)
invokes xsgetn()
(public member function of std::basic_streambuf<CharT,Traits>)
Put area
writes one character to the put area and advances the next pointer
(public member function of std::basic_streambuf<CharT,Traits>)
invokes xsputn()
(public member function of std::basic_streambuf<CharT,Traits>)
Putback
puts one character back in the input sequence
(public member function of std::basic_streambuf<CharT,Traits>)
moves the next pointer in the input sequence back by one
(public member function of std::basic_streambuf<CharT,Traits>)
Protected member functions
constructs a basic_streambuf object
(protected member function)
(C++11)
replaces a basic_streambuf object
(protected member function)
(C++11)
swaps two basic_streambuf objects
(protected member function)
Locales
[virtual]
reacts to a change of the associated locale
(virtual protected member function of std::basic_streambuf<CharT,Traits>)
Positioning
[virtual]
replaces the buffer with user-defined array, if permitted
(virtual protected member function of std::basic_streambuf<CharT,Traits>)
[virtual]
repositions the next pointer in the input sequence, output sequence, or both, using relative addressing
(virtual protected member function of std::basic_streambuf<CharT,Traits>)
[virtual]
repositions the next pointer in the input sequence, output sequence, or both using absolute addressing
(virtual protected member function of std::basic_streambuf<CharT,Traits>)
[virtual]
synchronizes the buffers with the associated character sequence
(virtual protected member function of std::basic_streambuf<CharT,Traits>)
Get area
[virtual]
obtains the number of characters available for input in the associated input sequence, if known
(virtual protected member function of std::basic_streambuf<CharT,Traits>)
[virtual]
reads characters from the associated input sequence to the get area
(virtual protected member function of std::basic_streambuf<CharT,Traits>)
[virtual]
reads characters from the associated input sequence to the get area and advances the next pointer
(virtual protected member function of std::basic_streambuf<CharT,Traits>)
[virtual]
reads multiple characters from the input sequence
(virtual protected member function of std::basic_streambuf<CharT,Traits>)
returns a pointer to the beginning, current character and the end of the get area
(protected member function)
advances the next pointer in the input sequence
(protected member function)
repositions the beginning, next, and end pointers of the input sequence
(protected member function)
Put area
[virtual]
writes multiple characters to the output sequence
(virtual protected member function of std::basic_streambuf<CharT,Traits>)
[virtual]
writes characters to the associated output sequence from the put area
(virtual protected member function of std::basic_streambuf<CharT,Traits>)
returns a pointer to the beginning, current character and the end of the put area
(protected member function)
advances the next pointer of the output sequence
(protected member function)
repositions the beginning, next, and end pointers of the output sequence
(protected member function)
Putback
[virtual]
puts a character back into the input sequence, possibly modifying the input sequence
(virtual protected member function of std::basic_streambuf<CharT,Traits>)