Submitted by tushar pramanick on Mon, 02/25/2013 - 12:42

The exit() Function

There is also a C library function, exit(), that can be used to cause a program to end. Because the exit() function is defined in a header file, stdlib.h, you have to include the header file at the beginning of your program।

Unlike main(), the exit() function itself does not return any values, but the argument to exit() indicates whether the program is terminated normally. A nonzero argument to the exit() function tells the operating system that the program has terminated abnormally.

Actually, you can replace return 0; in line 7 of Listing 2.1 with exit(0); and get a similar result after running the modified program.

Note that return and exit() can also be used in other functions. You'll see more examples in the rest of the book.

Listing 2.2 contains the program that uses exit() instead of return.

TYPE
Listing 2.2. A C program with exit().


  /* 02L02.c */
  #include <stdlib.h>
  #include <stdio.h>

 void main()   
 {      
   printf ("Howdy, neighbor! This is my first C program.\n"); 
   exit(0);   
 } 

 

After compiling the program in Listing 2.2, you should be able to run the program and get the same message, Howdy, neighbor! This is my first C program., printed out on the screen.

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.