php file and fopen functions not working - php

Question

I'm trying to learn about creating web bots and I'm working my way through a book called Webbots, Spiders, and Screen Scrapers by Michael Schrenk. In the book he gives example code for a basic bot that downloads a webpage. I have copied the code exactly as it is in the book (sans comments):
<?
$target = "http://www.schrenk.com/nostarch/webbots/hello_world.html";
$downloaded_page_array = file($target);
for($xx=0; $xx<count($downloaded_page_array); $xx++)
echo $downloaded_page_array[$xx];
?>
I put this code in a php file and uploaded to my site. When I navigate to it in the browser however, nothing happens. It just loads a blank page. No content.
Earlier I tried another snippet that the author provided, again, this one was copied EXACTLY from the book, only with this one I didn't really get a blank page, the page just tried to load until it eventually timed out. Never got the correct content back:
$target = "http://www.schrenk.com/nostarch/webbots/hello_world.html";
$file_handle = fopen($target, "r");
while (!feof($file_handle))
echo fgets($file_handle, 4096);
fclose($file_handle);
I have checked the URL to make sure the file exists and it does. I have no idea why this wouldn't work. I've read through how to use the file(); and fopen(); functions in PHP but from what I can tell they are both being used correctly. What am I doing wrong here?

Answer 1

Accessing URLs via fopen() is a bad idea. It requires you to have allow_url_fopen enabled in your PHP config, which opens the door to a vast number of exploits (hosters disable it for a reason).
Try using cURL functions instead: they will give you much more flexibility and control. PHP documentation gives you some great examples to start with.

Answer 2

Not fgets($file_handle, 4096) but fread($file_handle, 4096) ;
$target = "http://www.schrenk.com/nostarch/webbots/hello_world.html";
$file_handle = fopen($target, "r");
while (!feof($file_handle))
echo fread($file_handle, 4096);
fclose($file_handle);
Then later if you want to create a new file from the extracted text :
// extracting text operation
$target = "http://www.schrenk.com/nostarch/webbots/hello_world.html";
$file_handle = fopen($target, "r");
$getText = fread($file_handle, 4096);
fclose($file_handle);
// writing file operation
$writeHandle = fopen ("folder/text.txt","w"); // file will be created if not existed
$writeFile = fwrite($writeHandle,$getText );
fclose($writeHandle );

Answer 3

First you should put error_reporting(E_ALL); ini_set('display_errors', '1'); to your script to enable displaying errors in your script as AbraCadaver mentioned in his comment.
A reason could be, that allow_url_fopen is disabled on your hosting.
This option enables the URL-aware fopen wrappers that enable accessing URL object like files. Default wrappers are provided for the access of remote files using the ftp or http protocol, some extensions like zlib may register additional wrappers.
See: http://php.net/manual/en/filesystem.configuration.php#ini.allow-url-fopen
You can check that via:
var_dump(ini_get('allow_url_fopen'));
Your script requires true to run correct.
If allow_url_fopen is not true or 1 you can try to use file_get_contents() to load a url.
<?php
$homepage = file_get_contents('http://www.example.com/');
echo $homepage;
?>
See: http://php.net/manual/en/function.file-get-contents.php