openssl AES_cbc_encrypt

//    gcc -o myap openssl.c -lcrypto
#include "openssl/aes.h"
#include "string.h"
#include "stdio.h"


int main (int i, char** b){
  char filename[] = "file.txt";
  FILE *file = fopen ( filename, "r" );
  char key[] = "mysecretpassword";
  if (file != NULL) {
    char line [1000];
    char *p = line;
    char *array = line;
    while(fgets(line,sizeof line,file)!= NULL) {
      int ivSize = 16;
      int strLen = strlen(line) - ivSize;

      fprintf(stdout,"%s\n",line);
      char otherString[strLen + 1];

      strncpy(otherString, p, strLen);
      otherString[strLen] = '\0';

      printf("%s \n", otherString);//Here I got the Encrypted string
      array = array + strLen;
      printf("%s \n",array);//Here I got the IV

      char buffer[1000];
      AES_KEY dec_key;
      AES_set_decrypt_key(key, 128, &dec_key);
      AES_cbc_encrypt(otherString, buffer, strLen, &dec_key, array, AES_DECRYPT);
      printf("result is: %s\n", buffer);

      //Here how to decrypt the Cipher text using "IV" and "key"
    }
    fclose(file);
  }
  else {
    perror(filename);
  }
  return 0;
}