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std::basic_ofstream<CharT,Traits>::is_open

bool is_open() const;

Checks if the file stream has an associated file.

Effectively calls rdbuf()->is_open().

Parameters

(none).

Return value

true if the file stream has an associated file, false otherwise.

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 365 C++98 is_open was not declared with const qualifier declared with const qualifier

See also

opens a file and associates it with the stream
(public member function)
closes the associated file
(public member function)

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