标准C++当然没有从USB中读取的功能,但是让我们暂时忽略它的细节。
函数执行“真实”I/O的问题可以在标准C++中通过询问库函数有哪些来近似。
observable side effects
. 直接指向
Input/Output headers
现在当然还有
<filesystem>
.
(从C++引用复制:)
<iosfwd> forward declarations of all classes in the input/output library
<ios> std::ios_base class, std::basic_ios class template and several typedefs
<istream> std::basic_istream class template and several typedefs
<ostream> std::basic_ostream, std::basic_iostream class templates and several typedefs
<iostream> several standard stream objects
<fstream> std::basic_fstream, std::basic_ifstream, std::basic_ofstream class templates and several typedefs
<sstream> std::basic_stringstream, std::basic_istringstream, std::basic_ostringstream class templates and several typedefs
<syncstream> (since C++20) std::basic_osyncstream, std::basic_syncbuf, and typedefs
<strstream> (deprecated) std::strstream, std::istrstream, std::ostrstream
<iomanip> Helper functions to control the format of input and output
<streambuf> std::basic_streambuf class template
<cstdio> C-style input-output functions