Slide 2.3: Opening and closing files (cont.)

Opening and Closing Files (Cont.)

void open ( const char * filename, openmode mode );
Opens a file whose name is filename. The stream's file buffer is associated with the specified file to perform the I/O operations.

filename: String containing the name of the file to be opened.

mode: Flags describing the requested I/O mode for the file. This is an object of type ios_base::openmode, it generally consist of a combination of the following flags (member constants):

Bit	Effect
`app`	(append) Seek to the end of the stream before each output operation.
`ate`	(at end) Seek to the end of the stream when opening.
`binary`	Consider stream as binary rather than text.
`in`	Allow input operations on a stream.
`out`	Allow output operations on a stream.
`trunc`	(truncate) Truncate file to zero when opening.

The following demonstration shows how the open command works: