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std::basic_filebuf::close(3) C++ Standard Libary std::basic_filebuf::close(3)


std::basic_filebuf::close - std::basic_filebuf::close


std::basic_filebuf<CharT, Traits>* close();

If a put area exist (e.g. file was opened for writing), first calls
overflow(Traits::eof()) to write all pending output to the file, including any
unshift sequences.

If the most recently called function, out of underflow(), overflow(), seekpos(), and
seekoff(), was overflow(), then calls std::codecvt::unshift(), perhaps multiple
times, to determine the unshift sequence according to the imbued locale, and writes
that sequence to file with overflow(Traits::eof()).

Then, closes the file as if by calling std::fclose(), regardless of whether any of
the preceding calls succeeded or failed.

If any of the function calls made, including the call to std::fclose(), fails,
returns a null pointer. If any of the function calls made throws an exception, the
exception is caught and rethrown after closing the file. If the file is already
closed, returns a null pointer right away.

In any case, updates the private member variable that is accessed by is_open().



Return value

this on success, a null pointer on failure.


close() is typically called through the destructor of std::basic_filebuf (which, in
turn, is typically called by the destructor of std::basic_fstream.


This section is incomplete
Reason: no example

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 443 C++98 the file was written using changed to overflow(Traits::eof())
it was unclear how to handle
LWG 622 C++98 the it is rethrown after closing the
exception thrown during file

See also

is_open checks if the associated file is open
(public member function)
destructor destructs a basic_filebuf object and closes the file if it is open
[virtual] (virtual public member function)


* Todo no example