C to VB.net

//Caesar encryptor program
#include <stdio.h>
#include "sys\stat.h"

int main()
{
    int data, output;
    long long int count=0;
    struct stat statbuf;
    char enc_file[260], dec_file[260];
    int shift_phase;
    FILE * sourcefile;
    FILE * destfile;


    printf("\nShift phase: ");
    scanf("%d", &shift_phase);
    printf("\nFile path of target file: ");
    scanf("%s", enc_file);
    printf("\nOutput File Path: ");
    scanf("%s", dec_file);

    if ((sourcefile = fopen(enc_file, "rb"))== NULL)
    {
        printf("\nCan't open target file %s.\n", enc_file);
        return(4);
    }

    fflush(sourcefile);
    fstat(fileno(sourcefile), &statbuf);
    fclose(sourcefile);


    if ((sourcefile = fopen(enc_file, "rb")) == NULL)
    {
        printf("\nCan't open target file %s \n", enc_file);
        return(4);
    }

    if ((destfile=fopen(dec_file,"wb")) == NULL)
    {
        printf("\nCan't open destination file %s \n", dec_file);
        return(4);
    }


    while (count < (statbuf.st_size))
    {
        data=fgetc(sourcefile);
        output=(data+shift_phase);
        fputc(output,destfile);
        count++;
    }

    fclose(sourcefile);
    fclose(destfile);

    return 0;

}