Submitted by Anonymous (not verified) on Sun, 03/10/2013 - 20:58

Q What can you do with the enum data type?

    A The enum data type can be used to declare names that represent integer constants. You can use the default values held by enum names, or you can assign values to enum names and use them later in the program. The enum data type makes the C program more readable and easier to maintain, because you can use words which you understand as the names of enum, and you will only have to go to one place to update the values when needed.

    Q Why do you need to use the typedef keyword?

    A By using the typedef keyword, you can define your own names to represent the data types in C. You can represent complex data types in a single word and then use that word in subsequent variable declarations. In this way, you can avoid typing errors when writing a complex declaration over and over. Also, if a data type is changed in the future, you just need to update the typedef definition of the data type, which fixes every use of the typedef definition.

    Q Does a recursive function help to improve the performance of a program?

    A Not really. Normally, a recursive function only makes the implementations of some algorithms clearer and simpler. A recursive function may slow down the speed of a program because of the overhead of repeated function calls.

    Q What is the first command-line argument passed to a main() function?

    A The first command-line argument passed to a main() function is the executable filename entered by the user, plus the path to the executable file. The executable file is created from the program that contains the main() function. The first command-line argument is stored in the memory location referenced by the first element in the array of pointers that is declared as the second argument to the main() function.

 

Related Items

Using the Precision Specifier

Using the Precision Specifier

Aligning Output

Aligning Output
As you might have noticed in the previous section, all output is right-justified. In other words, by default, all output is placed on the right edge of the field, as long as the field width is longer than the width of the output.

 

Adding the Minimum Field Width

Adding the Minimum Field Width

Converting to Hex Numbers

Converting to Hex Numbers

Revisiting the printf() Function

Revisiting the printf() Function

The printf() function is the first C library function you used in this book to print out messages on the screen. printf() is a very important function in C, so it's worth it to spend more time on it.