title: How to write array with unsigned byte values to a binary file in PHP 5.6
body: <p>How can I write this array with unsigned bytes (0-255) to a binary file?</p>
  
  <p>The array look like this:</p>
  
  <p><em>note that I did not add any index because PHP automatically add the value to the next available index in the array variable when you use []. So the first my_PNG[]=137; is the same as my_PNG[0]=137;. Next time [] is used the next index 1 is returned and so on and so forth</em></p>
  
  <pre><code>my_PNG = array();
  my_PNG[]=137;
  my_PNG[]=80;
  my_PNG[]=78;
  my_PNG[]=71;
  my_PNG[]=13;
  my_PNG[]=10;
  my_PNG[]=26;
  my_PNG[]=10;
  my_PNG[]=0;
  my_PNG[]=0;
  my_PNG[]=0;
  my_PNG[]=13;
  my_PNG[]=73;
  my_PNG[]=72;
  my_PNG[]=68;
  my_PNG[]=82;
  my_PNG[]=0;
  my_PNG[]=0;
  my_PNG[]=0;
  my_PNG[]=1;
  my_PNG[]=0;
  my_PNG[]=0;
  my_PNG[]=0;
  my_PNG[]=1;
  my_PNG[]=8;
  my_PNG[]=6;
  my_PNG[]=0;
  my_PNG[]=0;
  my_PNG[]=0;
  my_PNG[]=31;
  my_PNG[]=21;
  my_PNG[]=196;
  my_PNG[]=137;
  my_PNG[]=0;
  my_PNG[]=0;
  my_PNG[]=0;
  my_PNG[]=13;
  my_PNG[]=73;
  my_PNG[]=68;
  my_PNG[]=65;
  my_PNG[]=84;
  my_PNG[]=120;
  my_PNG[]=156;
  my_PNG[]=99;
  my_PNG[]=96;
  my_PNG[]=96;
  my_PNG[]=96;
  my_PNG[]=248;
  my_PNG[]=15;
  my_PNG[]=0;
  my_PNG[]=1;
  my_PNG[]=4;
  my_PNG[]=1;
  my_PNG[]=0;
  my_PNG[]=95;
  my_PNG[]=229;
  my_PNG[]=195;
  my_PNG[]=75;
  my_PNG[]=0;
  my_PNG[]=0;
  my_PNG[]=0;
  my_PNG[]=0;
  my_PNG[]=73;
  my_PNG[]=69;
  my_PNG[]=78;
  my_PNG[]=68;
  my_PNG[]=174;
  my_PNG[]=66;
  my_PNG[]=96;
  my_PNG[]=130;
  </code></pre>
  
  <p>This is each byte in a PNG file with just one black pixel in it. 
  I want to write or somehow save this array to a file so it can be used as an PNG image on the server.</p>
  
  <p>I have tested:</p>
  
  <pre><code>file_put_contents('img.png', pack("C*",$my_PNG));
  </code></pre>
  
  <p>But it only save one byte to the file. I also tested a bunch of other things for the past 2 days now. So I finally wanted to get some help.</p>