PHP log into remote site and download csv
<?php
$username="";
$password="";
$url='';
$cookie="";
$postdata = 'email='.$username.'&pass='.$password;

$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, FALSE);
curl_setopt($ch, CURLOPT_USERAGENT, "Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US;       rv:1.8.1.6) Gecko/20070725 Firefox/2.0.0.6");
curl_setopt($ch, CURLOPT_TIMEOUT, 60);
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_COOKIEJAR, $cookie);
curl_setopt($ch, CURLOPT_REFERER, $url);
curl_setopt($ch, CURLOPT_POSTFIELDS, $postdata);
curl_setopt($ch, CURLOPT_POST, true);
$result = curl_exec($ch);
echo $result;
curl_close($ch);

<?php
$username="";
$password="";
$url='';
$csvurl='';
$cookie="";
$postdata = 'email='.$username.'&pass='.$password;

/*first log in*/
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, FALSE);
curl_setopt($ch, CURLOPT_USERAGENT, "Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US;       rv:1.8.1.6) Gecko/20070725 Firefox/2.0.0.6");
curl_setopt($ch, CURLOPT_TIMEOUT, 60);
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_COOKIEJAR, $cookie);
curl_setopt($ch, CURLOPT_REFERER, $url);
curl_setopt($ch, CURLOPT_POSTFIELDS, $postdata);
curl_setopt($ch, CURLOPT_POST, true);
$result = curl_exec($ch);
echo $result;

/*now download the file*/
curl_setopt($ch, CURLOPT_URL, $csvurl);
curl_setopt($ch, CURLOPT_REFERER, $url);
$result = curl_exec($ch);
echo $result;


curl_close($ch);
?>