[spanstream.members] # 31 Input/output library [[input.output]](./#input.output) ## 31.9 Span-based streams [[span.streams]](span.streams#spanstream.members) ### 31.9.6 Class template basic_spanstream [[spanstream]](spanstream#members) #### 31.9.6.4 Member functions [spanstream.members] [🔗](#lib:rdbuf,basic_spanstream) `basic_spanbuf* rdbuf() const noexcept; ` [1](#1) [#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/iostreams.tex#L10833) *Effects*: Equivalent to:return const_cast*>(addressof(*sb*)); [🔗](#lib:span,basic_spanstream) `std::span span() const noexcept; ` [2](#2) [#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/iostreams.tex#L10847) *Effects*: Equivalent to: return rdbuf()->span(); [🔗](#lib:span,basic_spanstream_) `void span(std::span s) noexcept; ` [3](#3) [#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/iostreams.tex#L10858) *Effects*: Equivalent to rdbuf()->span(s)[.](#3.sentence-1)