The C library functions are provided by the system and stored in the library. The C library function is also called an inbuilt function in C programming.

To use Inbuilt Function in C, you must include their respective header files, which contain prototypes and data definitions of the function.

C Program to Demonstrate the Use of Library Functions


void main()
  int i = -10, e = 2, d = 10; //Variables Defining and Assign values
  float rad = 1.43;
  double d1 = 3.0, d2 = 4.0;

  printf("%d\n", abs(i));
  printf("%f\n", sin(rad));
  printf("%f\n", cos(rad));
  printf("%f\n", exp(e));
  printf("%d\n", log(d));
  printf("%f\n", pow(d1, d2));    
Program Output: