PHP read body into byte array without using unpack [closed]

Question

Im writing a PHP script to run in apache2. I'm getting a byte array from a device that I need to parse into an object. When I do a $body = file_get_contents('php://input'), I get a string. Then I need to do a funky unpack('C*', $body). Now I have an array that has an extra element in the beginning, from the unpack process. It seems I'm trying too hard to do something that seems trivial.

Is there a way to just read the body as a byte array, and skip all the string conversion garbage? Come on PHP! Its just an array of bytes!

Answer 1

Trust me, believe or not there are no specific byte containers in PHP. You are doing it in the correct way. I have developed several binary algorithms in this language, it's really hard to understand when you come from other languages like C++ or Delphi.

In PHP the standard byte array container is the string. For example:

$myVar = file_get_contents("/folder/myfile.bin");

In this case myVar acts as string and also as array of bytes.

The only way to change bytes representation is performing pack and unpack operations.

$myByteArray= unpack("N*",$myvar); 
for($i = 0; $i < strlen($myByteArray); $i++)
{ 
    echo $myByteArray[$i].'<br/>'; 
}

Here you have some good explanations:

http://docstore.mik.ua/orelly/webprog/pcook/ch01_14.htm

http://www.codediesel.com/php/unpacking-binary-data/

And let me give you a last tip based on my experience: if you plan to migrate your PHP application to many different hardware arquitectures, take care of endianess on pack/unpack operations.