<?php
$city="Budapest"; // Your city
$country="hu"; // Two digit country code
$url="http://api.openweathermap.org/data/2.5/weather?q=".$city.",".$country."&appid=2de143494c0b295cca9337e1e96b00e0&units=metric";
$json=file_get_contents($url);
$data=json_decode($json,true);
$file = '/home/cs2d/sys/lua/weather.dat';
$current = file_get_contents($file);
$current .= $data['weather'][0]['main']."\n".$data['main']['temp']."\n";
// Write the contents back to the file
file_put_contents($file, $current);

$lines = file($current, FILE_IGNORE_NEW_LINES);
$remove = $current;
foreach($lines as $key => $line)
  if(stristr($line, $remove)) unset($lines[$key]);

$data = implode('\n', array_values($lines));

$file = fopen($path);
fwrite($file, $data);
fclose($file);