C2: Introduction to C

Question 1

What does hosted implementation of C mean?

Answer 1

It means full support for standard libraries. this type of C is used on top of OS.

Question 2

What is a freestanding implementation of C?

Answer 2

It means there is restricted library support. This is the case usually when C is run on hardware. ex: embedded systems

Question 3

Why include a header file in a C program?

Answer 3

to use standard libraries

Question 4

What are the steps for building C programs?

Answer 4

preprocessing, compiling, linking. (Using gcc usually executes all three steps automatically.)
in console:
>gcc -o hello hello.c
>./hello

Question 5

What is pre-processing?

Answer 5

 Pre-processing: processing directives,

modifying source file text

Question 6

What is compiling?

Answer 6

 Compiling: translating source code into
machine instructions (object code)

Question 7

What is linking?

Answer 7

 Linking: combining object code created
by compiler with other code to create a
single executable program

Question 8

What are comments?

Answer 8

They are text for documentation purposes and are mapped to whitespaces before preprocessing. (Neither pre-processor nor compiler sees them.)

Question 9

What is a variable

Answer 9

it has a name, a type and a value. It can be assigned values, do calculations and in-/output variables

Question 10

What is a function?

Answer 10

They are the basic means to avoid code
duplication and to structure our program
 Cannot be nested, grouped, etc.
 main is a special function and the only
mandatory one

Question 11

What are control structures in C?

Answer 11

Two types:
 Selection
• if statement
• switch statement
 Loops
• while loop
• do while loop
• for loop