std::basic_ofstream::basic_ofstream

From cppreference.com


basic_ofstream();	(1)

explicit basic_ofstream( const char* filename, ios_base::openmode mode = ios_base::out );	(2)

explicit basic_ofstream( const string& filename, ios_base::openmode mode = ios_base::out );	(3)	(since C++11)

basic_ofstream( basic_ofstream&& other );	(4)	(since C++11)

basic_ofstream( const basic_ofstream& rhs) = delete;	(5)	(since C++11)

Constructs new file stream.

1) Default constructor: constructs a stream that is not associated with a file: default-constructs the std::basic_filebuf and constructs the base with the pointer to this default-constructed std::basic_filebuf member.

2) First, performs the same steps as the default constructor, then asssociates the stream with a file by calling rdbuf()->open(filename, mode | std::ios_base::out).. If the open() call returns a null pointer, sets setstate(failbit).

3) Same as basic_ofstream(filename.c_str(), mode).

4) Move constructor. First, move-constructs the base class from other (which does not affect the rdbuf() pointer), then move-constructs the std::basic_filebuf member, then calls this->set_rdbuf() to install the new basic_filebuf as the rdbuf() pointer in the base class.

5) The copy-constructor is deleted: this class is not copyable.

[edit] Parameters

filename - the name of the file to be opened

mode

-

specifies stream open mode. It is bitmask type, the following constants are defined:


Constant	Explanation

`app`	seek to the end of stream before each write

`binary`	open in binary mode

`in`	open for reading

`out`	open for writing

`trunc`	discard the contents of the stream when opening

`ate`	seek to the end of stream immediately after open

other - another file stream to use as source

[edit] Example

run this code

#include <fstream>
#include <utility>
#include <string>
int main()
{
std::basic_ofstream f0;
    std::ofstream f1("test.bin", std::ios::binary);
    std::string name = "example.txt";
    std::ofstream f2(name);
    std::ofstream f3(std::move(f1));
}

[edit] See also


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

open	opens a file and configures it as the associated character sequence (public member function of `std::basic_filebuf`)

set_rdbuf	replaces the `rdbuf` without clearing its error state (protected member function)

(constructor)	constructs the object (public member function of `std::basic_ostream`)

Language
Standard library headers
Concepts
Utilities library
Strings library
Containers library
Algorithms library
Iterators library
Numerics library
Input/output library
Localizations library
Regular expressions library (C++11)
Atomic operations library (C++11)
Thread support library (C++11)