C program to convert binary to decimal using recursion

Write a C program to convert binary to decimal using recursion.

  #include <stdio.h>
  #include <string.h>
  #include <math.h>
  /* convert binary to decimal using recursion */
  void binaryToDecimal(char *binary, int *decimal, int *len) {
        static int num, i = 0;
        if (*len > 0) {
                /* parsing string from last character to start */
                *len = *len - 1;
                num = *(binary + *len) - '0';
                *decimal = *decimal + (num * pow(2, i++));
                binaryToDecimal(binary, decimal, len);
        }
        return;
  }

  int main() {
        char binary[256];
        int decimal = 0, len;

        /* get the input value from the user */
        printf("Enter your binary input:");
        fgets(binary, 256, stdin);
        binary[strlen(binary) - 1]= '\0';

        /* find the length of the given binary input */
        len = strlen(binary);

        /*
         * converts binary to decimal and it
         * stores the result in decimal
         */
        binaryToDecimal(binary, &decimal, &len);

        /* prints the resultant decimal value */
        printf("Decimal Value: %d\n", decimal);
        return 0;
  }

Note:
gcc binToDeci.c -lm => linked math library since we have used math function pow().

  Output:

  jp@jp-VirtualBox:~/$ ./a.out
  Enter your binary input:1111111111111111
  Decimal Value: 65535