Description:
------------
When I use stream_set_blocking() to make the standard input file handle non-blocking the script exits seemingly random. For example the $count output can have a last printed value anywhere from 200 to 3000.

Reproduce code:
---------------
<?
  
    if( ($stdin = fopen( 'php://stdin', 'r' )) === false )
    {                                                     
        echo 'Failed to open STDIN'."\n";
        exit();
    }          

    stream_set_blocking( $stdin, false );  
                                           
    $count = 0;                            
    while( 1 ) 
    {         
        echo 'Count: '.($count++)."\n";

        if( ($char = fread( $stdin, 1 )) != '' )
        {
            echo 'Char: '.$char."\n";
        }
        else
        {
            echo 'Fooo!'."\n";
        }
    }    


Expected result:
----------------
Script should run forever since it is in a while( 1 ) loop. This was done on purpose for testing purposes. At each pass of the loop it should print the current $count index, then if data exist in $stdin then it should print the character, otherwise print Fooo! to the screen.

Actual result:
--------------
Script does not run forever. Script exits and the last count printed can be anywhere from 200 to 3000 -- it seems kind of random. I ran the script through gdb and gdb indicates that the program (PHP) exits properly. Thus there is no backtrace to provide.