File Opening Modes:

“fstream” class allows to open a file in any specified mode with its objects.

All these mode specifiers are defined in “ios” class.

The different modes of opening a file are discussed below:

Mode	Meaning
in	Opens a file for reading
out	Opens a file for reading
app	Opens a file for appending
ate	Moves the file to end for reading or witing
binary	Opens a file in binary mode
nocreate	Error when opening if file does not exist
noreplace	Error when opening if file exists

Syntax:

            fstream f;

    f.open(filename, ios::in | ios::out)

Explanation:

The above code opens a file in both read and write modes. Programmer can both read into or write from a file.