Programming in C

16
Input and Output
Operations in C
ALL READING AND WRITING OF DATA up to this point has been done through your
terminal. 1 When you wanted to input some information, you either used the scanf or
getchar functions. All program results were displayed in your window with a call to the
printf function.
The C language itself does not have any special statements for performing input/output
(I/O) operations; all I/O operations in C must be carried out through function calls.
These functions are contained in the standard C library.
Recall the use of the following include statement from previous programs that used
the printf function:
#include
This include file contains function declarations and macro definitions associated with the
I/O routines from the standard library.Therefore, whenever using a function from this
library, you should include this file in your program.
In this chapter, you learn about many of the I/O functions that are provided in the
standard library. Unfortunately, space does not permit lengthy details about these functions
or discussions of each function that is offered. Refer to Appendix B,“The Standard
C Library,” for a list of most of the functions in the library.
1. Again, the term “terminal” is used loosely here to typically mean the active window in which
you are running your program, or the window in which the output from your program appears.
On some systems the output window is called the “console.”