PHP: sendSMS via cURL

sendSMS.php

<?php
 	/**
 	 * a function for sending sms using curl.
 	 * @param  integer $to -must be a valid 10 digit mobile number
 	 * @param  string $msg -must be valid message.
 	 * @return string
 	 */
	function sendSms($to,$msg)
	{      
	$username = ""; // The username of SENDER.
	$password = ""; // The password of SENDER.
	$sendername = ""; // SENDER ID or SENDER NAME
	$msg = urlencode($msg);
	$url = "http://sms2.at54.com/reseller/sendsms.jsp?user=$username&password=$password&mobiles=$to&sms=$msg&senderid=$sendername"; // The API URL for cURL request, change it accordingly.
	$ch=curl_init();
	curl_setopt($ch, CURLOPT_URL,  $url);
	curl_setopt($ch, CURLOPT_HEADER, 0);
	curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
	curl_exec($ch);
	curl_close($ch);
	return $url;
	}
 ?>