Input is the process of getting data from the user and Output is the activity of displaying a message or a result of program to the user. Basically I/O operations make possible the communication between the user and the program. Input and Output operations performing with standard I/O devices that is keyboard and monitor are called as Standard I/O operations. There are some other type of I/O operations like file I/O operations which will be discussed later in this course.
In C Language, all the I/O is based on the functions only. Moreover those functions are pre-defined functions existed in the library of header files like stdio.h, conio.h etc. We have to attach the code of the respective functions to our program in order to use a i/o function. For example, to use printf and scanf functions we have to link their definitions from stdio.h to our program.
There are Two types of I/O Functions
- Formatted
- Unformatted