PHP Strange behaviour of foreach

I've a code:

$csv = file('some.csv');

foreach($csv as $value)
{
    echo $value;
}

Everything is OK until the request method was POST - then the last element of an array is missing (thought it's showing properly by print_r($csv)).

What may the problem be? That's the WHOLE CODE!

Try it:

$csv = file('some.csv');

// Loop through our array
foreach ($cvs as $line_num => $line) {
    echo $line."<br />\n";
}