Standard library header <sstream>

 

C++

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Feature test macros(C++20)

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Concepts library(C++20)

Diagnostics library

Memory management library

Metaprogramming library(C++11)

General utilities library

Containers library

Iterators library

Ranges library(C++20)

Algorithms library

Strings library

Text processing library

Numerics library

Date and time library

Input/output library

Filesystem library(C++17)

Concurrency support library(C++11)

Execution control library(C++26)

Technical specifications

Symbols index

External libraries

 

Standard library headers

Language support <cfloat> <climits> <compare>(C++20) <contracts>(C++26) <coroutine>(C++20) <csetjmp> <csignal> <cstdarg> <cstddef> <cstdint>(C++11) <cstdlib> <exception> <initializer_list>(C++11)    <limits> <new> <source_location>(C++20) <stdfloat>(C++23) <typeinfo> <version>(C++20) Concepts <concepts>(C++20) Diagnostics <cassert> <cerrno> <debugging>(C++26) <stacktrace>(C++23) <stdexcept> <system_error>(C++11) Memory management <memory> <memory_resource>(C++17) <scoped_allocator>(C++11) Metaprogramming <type_traits>(C++11) <ratio>(C++11)

General utilities <any>(C++17) <bitset> <bit>(C++20) <charconv>(C++17) <expected>(C++23) <format>(C++20) <functional> <optional>(C++17) <stdbit.h>(C++26) <tuple>(C++11) <typeindex>(C++11) <utility> <variant>(C++17) Containers <array>(C++11) <deque> <flat_map>(C++23) <flat_set>(C++23) <forward_list>(C++11) <hive>(C++26) <inplace_vector>(C++26)    <list> <map> <mdspan>(C++23) <queue> <set> <span>(C++20) <stack> <unordered_map>(C++11) <unordered_set>(C++11) <vector> Iterators <iterator> Ranges <generator>(C++23) <ranges>(C++20)

Algorithms <algorithm> <numeric> Strings <cctype> <cstring> <cuchar>(C++11) <cwchar> <cwctype> <string_view>(C++17) <string> Text processing <clocale> <codecvt>(C++11/17/26*) <locale> <regex>(C++11) <text_encoding>(C++26)    Numerics <cfenv>(C++11) <cmath> <complex> <linalg>(C++26) <numbers>(C++20) <random>(C++11) <simd>(C++26) <stdckdint.h>(C++26) <valarray> Time <chrono>(C++11) <ctime> C compatibility <ccomplex>(C++11/17/20*) <ciso646>(until C++20) <cstdalign>(C++11/17/20*) <cstdbool>(C++11/17/20*) <ctgmath>(C++11/17/20*)

Input/output <cinttypes>(C++11) <cstdio> <filesystem>(C++17) <fstream> <iomanip> <iosfwd> <iostream> <ios> <istream> <ostream> <print>(C++23) <spanstream>(C++23) <sstream> <streambuf> <strstream>(C++98/26*) <syncstream>(C++20) Concurrency support <atomic>(C++11) <barrier>(C++20) <condition_variable>(C++11) <future>(C++11) <hazard_pointer>(C++26) <latch>(C++20) <mutex>(C++11) <rcu>(C++26) <semaphore>(C++20) <shared_mutex>(C++14) <stdatomic.h>(C++23) <stop_token>(C++20) <thread>(C++11) Execution support <execution>(C++17)

 

This header is part of the Input/Output library.

Classes
basic_stringbuf	implements raw string device (class template)
basic_istringstream	implements high-level string stream input operations (class template)
basic_ostringstream	implements high-level string stream output operations (class template)
basic_stringstream	implements high-level string stream input/output operations (class template)
stringbuf	std::basic_stringbuf<char> (typedef)
wstringbuf	std::basic_stringbuf<wchar_t> (typedef)
istringstream	std::basic_istringstream<char> (typedef)
wistringstream	std::basic_istringstream<wchar_t> (typedef)
ostringstream	std::basic_ostringstream<char> (typedef)
wostringstream	std::basic_ostringstream<wchar_t> (typedef)
stringstream	std::basic_stringstream<char> (typedef)
wstringstream	std::basic_stringstream<wchar_t> (typedef)
Functions
std::swap(std::basic_stringbuf) (C++11)	specializes the std::swap algorithm (function template)
std::swap(std::basic_istringstream) (C++11)	specializes the std::swap algorithm (function template)
std::swap(std::basic_ostringstream) (C++11)	specializes the std::swap algorithm (function template)
std::swap(std::basic_stringstream) (C++11)	specializes the std::swap algorithm (function template)

Synopsis

namespace std {template<class CharT, class Traits = char_traits<CharT>, class Allocator = allocator<CharT>>class basic_stringbuf;   using stringbuf = basic_stringbuf<char>;using wstringbuf = basic_stringbuf<wchar_t>;   template<class CharT, class Traits = char_traits<CharT>, class Allocator = allocator<CharT>>class basic_istringstream;   using istringstream = basic_istringstream<char>;using wistringstream = basic_istringstream<wchar_t>;   template<class CharT, class Traits = char_traits<CharT>, class Allocator = allocator<CharT>>class basic_ostringstream;using ostringstream = basic_ostringstream<char>;using wostringstream = basic_ostringstream<wchar_t>;   template<class CharT, class Traits = char_traits<CharT>, class Allocator = allocator<CharT>>class basic_stringstream;using stringstream = basic_stringstream<char>;using wstringstream = basic_stringstream<wchar_t>;}

Class template std::basic_stringbuf

namespace std {template<class CharT, class Traits = char_traits<CharT>, class Allocator = allocator<CharT>>class basic_stringbuf :public basic_streambuf<CharT, Traits>{public:using char_type = CharT;using int_type =typename Traits::int_type;using pos_type =typename Traits::pos_type;using off_type =typename Traits::off_type;using traits_type = Traits;using allocator_type = Allocator;   // constructors basic_stringbuf(): basic_stringbuf(ios_base::in| ios_base::out){}explicit basic_stringbuf(ios_base::openmode which);explicit basic_stringbuf(const basic_string<CharT, Traits, Allocator>& s, ios_base::openmode which = ios_base::in| ios_base::out);explicit basic_stringbuf(const Allocator& a): basic_stringbuf(ios_base::in| ios_base::out, a){} basic_stringbuf(ios_base::openmode which, const Allocator& a);explicit basic_stringbuf( basic_string<CharT, Traits, Allocator>&& s, ios_base::openmode which = ios_base::in| ios_base::out);template<class SAlloc> basic_stringbuf(const basic_string<CharT, Traits, SAlloc>& s, const Allocator& a): basic_stringbuf(s, ios_base::in| ios_base::out, a){}template<class SAlloc> basic_stringbuf(const basic_string<CharT, Traits, SAlloc>& s, ios_base::openmode which, const Allocator& a);template<class SAlloc>explicit basic_stringbuf(const basic_string<CharT, Traits, SAlloc>& s, ios_base::openmode which = ios_base::in| ios_base::out); basic_stringbuf(const basic_stringbuf&)= delete; basic_stringbuf(basic_stringbuf&& rhs); basic_stringbuf(basic_stringbuf&& rhs, const Allocator& a);   // assign and swap basic_stringbuf& operator=(const basic_stringbuf&)= delete; basic_stringbuf& operator=(basic_stringbuf&& rhs);void swap(basic_stringbuf& rhs)noexcept(see below);   // getters and setters allocator_type get_allocator()constnoexcept;   basic_string<CharT, Traits, Allocator> str()const&;template<class SAlloc> basic_string<CharT,Traits,SAlloc> str(const SAlloc& sa)const; basic_string<CharT, Traits, Allocator> str()&&; basic_string_view<CharT, Traits> view()constnoexcept;   void str(const basic_string<CharT, Traits, Allocator>& s);template<class SAlloc>void str(const basic_string<CharT, Traits, SAlloc>& s);void str(basic_string<CharT, Traits, Allocator>&& s);   protected:// overridden virtual functions int_type underflow() override; int_type pbackfail(int_type c = Traits::eof()) override; int_type overflow (int_type c = Traits::eof()) override; basic_streambuf<CharT, Traits>* setbuf(CharT*, streamsize) override;   pos_type seekoff(off_type off, ios_base::seekdir way, ios_base::openmode which = ios_base::in| ios_base::out) override; pos_type seekpos(pos_type sp, ios_base::openmode which = ios_base::in| ios_base::out) override;   private: ios_base::openmode mode;// exposition only basic_string<CharT, Traits, Allocator> buf;// exposition onlyvoid init_buf_ptrs();// exposition only};   template<class CharT, class Traits, class Allocator>void swap(basic_stringbuf<CharT, Traits, Allocator>& x, basic_stringbuf<CharT, Traits, Allocator>& y)noexcept(noexcept(x.swap(y)));}

Class template std::basic_istringstream

namespace std {template<class CharT, class Traits = char_traits<CharT>, class Allocator = allocator<CharT>>class basic_istringstream :public basic_istream<CharT, Traits>{public:using char_type = CharT;using int_type =typename Traits::int_type;using pos_type =typename Traits::pos_type;using off_type =typename Traits::off_type;using traits_type = Traits;using allocator_type = Allocator;   // constructors basic_istringstream(): basic_istringstream(ios_base::in){}explicit basic_istringstream(ios_base::openmode which);explicit basic_istringstream(const basic_string<CharT, Traits, Allocator>& s, ios_base::openmode which = ios_base::in); basic_istringstream(ios_base::openmode which, const Allocator& a);explicit basic_istringstream( basic_string<CharT, Traits, Allocator>&& s, ios_base::openmode which = ios_base::in);template<class SAlloc> basic_istringstream(const basic_string<CharT, Traits, SAlloc>& s, const Allocator& a): basic_istringstream(s, ios_base::in, a){}template<class SAlloc> basic_istringstream(const basic_string<CharT, Traits, SAlloc>& s, ios_base::openmode which, const Allocator& a);template<class SAlloc>explicit basic_istringstream(const basic_string<CharT, Traits, SAlloc>& s, ios_base::openmode which = ios_base::in); basic_istringstream(const basic_istringstream&)= delete; basic_istringstream(basic_istringstream&& rhs);   // assign and swap basic_istringstream& operator=(const basic_istringstream&)= delete; basic_istringstream& operator=(basic_istringstream&& rhs);void swap(basic_istringstream& rhs);   // members basic_stringbuf<CharT, Traits, Allocator>* rdbuf()const; basic_string<CharT, Traits, Allocator> str()const&;template<class SAlloc> basic_string<CharT,Traits,SAlloc> str(const SAlloc& sa)const; basic_string<CharT, Traits, Allocator> str()&&; basic_string_view<CharT, Traits> view()constnoexcept;   void str(const basic_string<CharT, Traits, Allocator>& s);template<class SAlloc>void str(const basic_string<CharT, Traits, SAlloc>& s);void str(basic_string<CharT, Traits, Allocator>&& s);   private: basic_stringbuf<CharT, Traits, Allocator> sb;// exposition only};   template<class CharT, class Traits, class Allocator>void swap(basic_istringstream<CharT, Traits, Allocator>& x, basic_istringstream<CharT, Traits, Allocator>& y);}

Class template std::basic_ostringstream

namespace std {template<class CharT, class Traits = char_traits<CharT>, class Allocator = allocator<CharT>>class basic_ostringstream :public basic_ostream<CharT, Traits>{public:using char_type = CharT;using int_type =typename Traits::int_type;using pos_type =typename Traits::pos_type;using off_type =typename Traits::off_type;using traits_type = Traits;using allocator_type = Allocator;   // constructors basic_ostringstream(): basic_ostringstream(ios_base::out){}explicit basic_ostringstream(ios_base::openmode which);explicit basic_ostringstream(const basic_string<CharT, Traits, Allocator>& s, ios_base::openmode which = ios_base::out); basic_ostringstream(ios_base::openmode which, const Allocator& a);explicit basic_ostringstream( basic_string<CharT, Traits, Allocator>&& s, ios_base::openmode which = ios_base::out);template<class SAlloc> basic_ostringstream(const basic_string<CharT, Traits, SAlloc>& s, const Allocator& a): basic_ostringstream(s, ios_base::out, a){}template<class SAlloc> basic_ostringstream(const basic_string<CharT, Traits, SAlloc>& s, ios_base::openmode which, const Allocator& a);template<class SAlloc>explicit basic_ostringstream(const basic_string<CharT, Traits, SAlloc>& s, ios_base::openmode which = ios_base::out); basic_ostringstream(const basic_ostringstream&)= delete; basic_ostringstream(basic_ostringstream&& rhs);   // assign and swap basic_ostringstream& operator=(const basic_ostringstream&)= delete; basic_ostringstream& operator=(basic_ostringstream&& rhs);void swap(basic_ostringstream& rhs);   // members basic_stringbuf<CharT, Traits, Allocator>* rdbuf()const;   basic_string<CharT, Traits, Allocator> str()const&;template<class SAlloc> basic_string<CharT,Traits,SAlloc> str(const SAlloc& sa)const; basic_string<CharT, Traits, Allocator> str()&&; basic_string_view<CharT, Traits> view()constnoexcept;   void str(const basic_string<CharT, Traits, Allocator>& s);template<class SAlloc>void str(const basic_string<CharT, Traits, SAlloc>& s);void str(basic_string<CharT, Traits, Allocator>&& s);   private: basic_stringbuf<CharT, Traits, Allocator> sb;// exposition only};   template<class CharT, class Traits, class Allocator>void swap(basic_ostringstream<CharT, Traits, Allocator>& x, basic_ostringstream<CharT, Traits, Allocator>& y);}

Class template std::basic_stringstream

namespace std {template<class CharT, class Traits = char_traits<CharT>, class Allocator = allocator<CharT>>class basic_stringstream :public basic_iostream<CharT, Traits>{public:using char_type = CharT;using int_type =typename Traits::int_type;using pos_type =typename Traits::pos_type;using off_type =typename Traits::off_type;using traits_type = Traits;using allocator_type = Allocator;   // constructors basic_stringstream(): basic_stringstream(ios_base::out| ios_base::in){}explicit basic_stringstream(ios_base::openmode which);explicit basic_stringstream(const basic_string<CharT, Traits, Allocator>& s, ios_base::openmode which = ios_base::out| ios_base::in); basic_stringstream(ios_base::openmode which, const Allocator& a);explicit basic_stringstream( basic_string<CharT, Traits, Allocator>&& s, ios_base::openmode which = ios_base::out| ios_base::in);template<class SAlloc> basic_stringstream(const basic_string<CharT, Traits, SAlloc>& s, const Allocator& a): basic_stringstream(s, ios_base::out| ios_base::in, a){}template<class SAlloc> basic_stringstream(const basic_string<CharT, Traits, SAlloc>& s, ios_base::openmode which, const Allocator& a);template<class SAlloc>explicit basic_stringstream(const basic_string<CharT, Traits, SAlloc>& s, ios_base::openmode which = ios_base::out| ios_base::in); basic_stringstream(const basic_stringstream&)= delete; basic_stringstream(basic_stringstream&& rhs);   // assign and swap basic_stringstream& operator=(const basic_stringstream&)= delete; basic_stringstream& operator=(basic_stringstream&& rhs);void swap(basic_stringstream& rhs);   // members basic_stringbuf<CharT, Traits, Allocator>* rdbuf()const;   basic_string<CharT, Traits, Allocator> str()const&;template<class SAlloc> basic_string<CharT,Traits,SAlloc> str(const SAlloc& sa)const; basic_string<CharT, Traits, Allocator> str()&&; basic_string_view<CharT, Traits> view()constnoexcept;   void str(const basic_string<CharT, Traits, Allocator>& s);template<class SAlloc>void str(const basic_string<CharT, Traits, SAlloc>& s);void str(basic_string<CharT, Traits, Allocator>&& s);   private: basic_stringbuf<CharT, Traits> sb;// exposition only};   template<class CharT, class Traits, class Allocator>void swap(basic_stringstream<CharT, Traits, Allocator>& x, basic_stringstream<CharT, Traits, Allocator>& y);}

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR	Applied to	Behavior as published	Correct behavior
LWG 170	C++98	the definitions of traits_type were missing in the synopses of std::basic_ostringstream and std::basic_stringstream	added
LWG 251	C++98	the definitions of allocator_type were missing in the synopses of std::basic_stringbuf, std::basic_istringstream std::basic_ostringstream and std::basic_stringstream	added