在Windows，Linux和Mac上为同一图像创建不同的哈希值

Question

i am creating Hash values with following code, now what happens is that when i test the hash value on Windows local Xampp server i get hash value which is different for same code that runs on Linux.

  move_uploaded_file($_FILES["file"]["tmp_name"], "upload/" . $newname);
    "Stored in: " . "upload/" . $_FILES["file"]["name"];
    $image = "upload/" . $newname;
    $sign = md5(file_get_contents($image));

Now i dont know why is this happening. For the same code that i just pasted above.

EDIT: Opening question again. The solution i found worked only for Linux which means linux and windows now give me same hash but when an image is uploaded from Mac(IOS) it is still generating different Hash.

Answer 1

Ok i found answer to my question, I still dont know why there are two different hashes been generated for the same code in windows and Linux

move_uploaded_file($_FILES["file"]["tmp_name"], "upload/" . $newname); 
    "Stored in: " . "upload/" . $_FILES["file"]["name"];
    $image = "upload/" . $newname;
    $sign = md5(file_get_contents($image));//This is code block that i was implmenting before solution

What i tried here was i replaced my above code with following code

 move_uploaded_file($_FILES["file"]["tmp_name"], "upload/" . $newname);
        "Stored in: " . "upload/" . $_FILES["file"]["name"];
        $image = "upload/" . $newname;
        $sign = md5_file($image);// Changed here

From this i think Hash values may be same when generated by md5() but if this function accepts file as input then hash values are calculated differently, i dont know if this is a PHP side issue or really OS level issue but if i go on with using md5_file() for generating hash of file i dont get different hash.