বিভিন্ন More Data Types এবং Functions

Submitted by administrator on Mon, 01/02/2012 - 16:19

In Chapter 4, "Data Types and Names in C," you learned about most of the data types, such as char, int, float, and double. In Hour 15, "Functions in C," you learned the basics of using functions in C. In this hour, you'll learn more about data types and functions from the following topics:

    The enum data type
    The typedef statement
    Function recursion
    Command-line arguments



Summary

  •     The enum (that is, enumerated) data type can be used to declare named integer constants.
  •     By default, the first enum name starts with the value of 0. Each name in the rest of the list increases by one from the value contained by the name on its left side.
  •     If needed, you can assign any integer values to enumerated names.
  •     You can create your own names for data types with the help of the typedef keyword. Those names can then be used as synonyms for the data types.
  •     In ANSI C, there is a header file called stddef.h that contains a dozen typedef definitions.
  •     A function in C can be made to call itself. Such a function is said to be recursive.
  •     You can use command-line arguments to pass information to the main() function in your program.
  •     There are two built-in arguments to the main() function. The executable filename you entered from the operating system's command line is counted as the first command-line argument.
  •     The first built-in argument receives the number of command-line arguments entered by the user. The second built-in argument is a pointer to an array of pointers that refers to the strings of command-line arguments.



   

Related Items

The #define and #undef Directives

The #define and #undef Directives

The #define directive is the most common preprocessor directive, which tells the preprocessor to replace every occurrence of a particular character string (that is, a macro name) with a specified value (that is, a macro body).

The C Preprocessor Versus the Compiler

The C Preprocessor Versus the Compiler

One important thing you need to remember is that the C preprocessor is not part of the C compiler.

What Is the C Preprocessor?

If there is a constant appearing in several places in your program, it's a good idea to associate a symbolic name to the constant, and then use the symbolic name to replace the constant throughout the program. There are two advantages to doing so. First, your program will be more readable.

Exercises : Answer the following Question

To help solidify your understanding of this hour's lesson, you are encouraged to answer the quiz questions and finish the exercises provided in the Workshop before you move to the next lesson.

Question and Answer

    Q Why is random access to a disk file necessary?