Submitted by tushar pramanick on Mon, 02/25/2013 - 11:35

Questions and Answers


Q Why do you need to put comments into your programs?
A Comments help us document what a program, or a special portion of a program, does. Especially when a program becomes very complex, we need to write comments to mark different parts in the program.

 

Q Why is the main() function needed in your program?
A The execution of a C program starts and ends with the main() function. Without the main() function, the computer does not know where to start to run a program.

 

Q What does the #include directive do?
A The #include directive is used to include header files that contain the declarations to the functions used in your C program. In other words, the #include directive tells the C preprocessor to look into directories and find the specified header file.

 

Q Why do you need a linker?
A After compiling, some function code may still be missing in the object file of a program. A linker must then be used to link the object file to the C standard library or other user-generated libraries and include the missing function code so that an executable file can be created.

 

 

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In line 4 of Listing 2.1, you see this function:

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You may notice that the void word has been added into the C program in Listing 2.2. void is a keyword for a data type in C. When a void is placed prior to a function name, it indicates that the function does not return a value.

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Let's now move to line 2 in the C program of Listing 2.1:

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