Next: Reading and writing FILES Up: Input and Output (I/O) Previous: scanf

Files

Files are the most common form of a stream.

The first thing we must do is open a file. The function fopen() does this:

FILE *fopen(char *name, char *mode)

fopen returns a pointer to a FILE. The name string is the name of the file on disc that we wish to access. The mode string controls our type of access. If a file cannot be accessed for any reason a NULL pointer is returned.

To open a file we must have a stream (file pointer) that points to a FILE structure.

So to open a file, called myfile.dat for reading we would do:



Dave.Marshall@cm.cf.ac.uk
Wed Sep 14 10:06:31 BST 1994