پچ کردن مقدار آدرس آفست یک فایل

# include <iostream>
using namespace std;
void patch_file(std::string filename,int offset, int value);
void main ()
{
// File name, Offset, Value to patch
patch_file("test.bin", 0x0F, 0xFF);
}
void patch_file(std::string filename,int offset, int value) 
{
// File Size
FILE *file_size = NULL;                                    
file_size = fopen(filename.c_str(),"rb");
fseek(file_size,0,SEEK_END);
int size = ftell(file_size);
fclose (file_size);
// File to Buffer
FILE *read_file = NULL;                                    
read_file = fopen(filename.c_str(),"rb");                
unsigned char *buffer = new unsigned char[size];
fread(buffer,1,size,read_file);
fclose (read_file);
// Backup from File
FILE *backup_file = NULL;                                
char backup[20];
strcpy(backup, filename.c_str());
strcat (backup, ".backup");
backup_file = fopen(backup,"wb");
fwrite(buffer,1,size,backup_file);
fclose (backup_file);
// Patch value to buffer
buffer [offset] = value;                                
// Buffer to File
FILE *write_file = NULL;                                
write_file = fopen(filename.c_str(),"wb");                
fwrite(buffer,1,size,write_file);
fclose (write_file);
}