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() .
[edit] Parameters
(none)
[edit] Return value
this on success, a null pointer on failure.
[edit] Notes
close() is typically called through the destructor of std::basic_filebuf (which, in turn, is typically called by the destructor of std::basic_fstream .
[edit] Example
Reason: no example
[edit] 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 overflow(EOF ) | changed to overflow(Traits::eof()) |
| LWG 622 | C++98 | it was unclear how to handle the exception thrown during closing |
it is rethrown after closing the file |
[edit] See also
basic_filebuf object and closes the file if it is open (virtual public member function) [edit]