https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91653
Liu Hao <lh_mouse at 126 dot com> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |lh_mouse at 126 dot com
--- Comment #5 from Liu Hao <lh_mouse at 126 dot com> ---
This may be inconsistency (if not necessarily a defect) in the C++ standard,
since both `basic_ostream::{put,write}`, as UnformattedOutputFunctions, set
`badbit` in case of output failure, but `operator<<(basic_streambuf*)` doesn't.
Nevertheless GCC is doing the right thing and conform to all standards.
It should also be noted that if `operator<<(basic_streambuf*)` could not
extract any character, `failbit` is set on the output stream. Thus correct use
of this function requires a loop, as follows:
```
bool copy_stream(std::ostream& os, std::istream& is)
{
while(os && (is.rdbuf()->sgetc()
!= std::istream::traits_type::eof()))
os << is.rdbuf();
return !!os;
}
```
Anyway, it is not a bug in libstdc++.
