C library functions are provided by the system and stored in the library. In C programming, C library functions are also called inbuilt functions.
To use Inbuilt Function in C, you must include their respective header files containing prototypes and data definitions.
C Program to Demonstrate the Use of Library Functions
Example:
#include<stdio.h>
#include<ctype.h>
#include<math.h>
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: