Include Files

Include Files

Also called "header files"; typically have extensions such as .h or .hpp; examples are string.h, math.h, and iostream.h

They contain all of the declarations for functions provided by the C++ runtime libraries

There are hundreds of them in a large system such as UNIX; Turbo C++ has about 50 or so

Only the most trivial programs do not use any functions from the standard libraries, and therefore, do not need to include any header files

You will almost always need to include iostream.h; it is required if you want to print anything to the screen

The syntax for using include files is:

   #include <filename.h>

To include more than one, use multiple statements:

   #include <math.h>
   #include <iostream.h
   #include <string.h>