C Programming 01/2

Question 1

What is #include?

Answer 1

Pre-processor directive which inserts a file into the source code. These are commonly called ‘header files’ and given the extension ‘.h’

Question 2

What is #define?

Answer 2

Pre-processor directive which allows the definition of macros within your source code

Question 3

What is the difference between declare and defining?

Answer 3

Declaring a variable or function creates the name but no value/functionality
Defining a variable or function creates the name and associated value/functionality

Question 4

What is a function prototype?

Answer 4

A function prototype lets you declare a function, without its body

Question 5

What is a header file?

Answer 5

A file which is designed to be included in multiple files, and often contain function prototypes

Question 6

What is typedef?

Answer 6

Use typedef to give new names to types
e.g
typedef oldname newname1, newname2;
or
typedef unsigned int day, month;

Question 7

What is casting?

Answer 7

• Converts a value from one type to another.
• Casting may be implicit or explicit.
• There is no error checking on casting.

Question 8

What is static?

Answer 8

This variable or function is unique to this file

Question 9

What is extern?

Answer 9

This variable will be declared in some other file but I will use it here