ofstream::ofstream

ofstream();

ofstream( const char* szName, int nMode = ios::out, int nProt = filebuf::openprot );

ofstream( filedesc fd );

ofstream( filedesc fd, char* pch, int nLength );

Parameters

szName

The name of the file to be opened during construction.

nMode

An integer that contains mode bits defined as ios enumerators that can be combined with the bitwise OR ( | ) operator. The nMode parameter must have one of the following values:

nProt

The file protection specification; defaults to the static integer filebuf::openprot that is equivalent to filebuf::sh_compat. The possible nProt values are:

fd

A file descriptor as returned by a call to the run-time function _open or _sopen; filedesc is a typedef equivalent to int.

pch

Pointer to a previously allocated reserve area of length nLength. A NULL value (or nLength = 0) indicates that the stream will be unbuffered.

nLength

The length (in bytes) of the reserve area (0 = unbuffered).

Remarks

The four ofstream constructors are:

Constructor Description
ofstream() Constructs an ofstream object without opening a file.
ofstream( const char*, int, int ) Contructs an ofstream object, opening the specified file.
ofstream( filedesc ) Constructs an ofstream object that is attached to an open file.
ofstream( filedesc, char*, int ) Constructs an ofstream object that is associated with a filebuf object. The filebuf object is attached to an open file and to a specified reserve area.

All ofstream constructors construct a filebuf object. The first three use an internally allocated reserve area, but the fourth uses a user-allocated area. The user-allocated area is not automatically released during destruction.

ofstream OverviewOutput Stream Classes