Perl project #3

• The arguments passed from the command line are to be treated as file names or directory names. Your script should perform a check for each command line argument to find out is that a name of existing file or name of the directory.
• For each existing file name specified as parameter, the script should read the file and search its contents for links to pages located on remote servers. In other words, your should look for HTML links like:

  <a href="http://remote_page_address" ...>Link name</a> 

• For each link found, the script should connect to the remote server and request the page specified. Once the page received, the script will read th error code, analyses it, and prints an error message if the page was not found (dead link). In the error message you should specify the name of the directory, name of the file, link title, and the address of the remote page.
• For each directory name specified in the command line the script should perform the same checking for each HTML, HTM, and PHP file in the directory. Note: You do not have recursively go into sub-directories.
• If no arguments is given to the script, the script should look for dead links in all HTML files in the current directory.

The following code illustrates how you can get a web page from a remote server.

use IO::Socket;

sub GetHTTPHeader
{
   my ($server, $page) = @_;
   if( $server =~ /:(\d+)$/ ){
      my $port = $1;
   }
   else{
      $port = 80;
   }
   $page = "/" . $page unless $page =~ /^\//;
	my $sock = new IO::Socket::INET (
					 PeerAddr => $server,
					 PeerPort => $port,
					 Proto => 'tcp',
					);
	die "Could not create socket: $!\n" unless $sock;
	
	# sending HTTP 1.1 request
	print $sock "HEAD http://$server:$port$page HTTP/1.1\nHost: $server:$port\nConnection: Closed\n\n";
	
	@header = <$sock>;
	close($sock);
	return @header;
}

sub GetWebPage
{
   my ($server, $page) = @_;
   if( $server =~ /:(\d+)$/ ){
      my $port = $1;
   }
   else{
      $port = 80;
   }
   $page = "/" . $page unless $page =~ /^\//;
	my $sock = new IO::Socket::INET (
					 PeerAddr => $server,
					 PeerPort => $port,
					 Proto => 'tcp',
					);
	die "Could not create socket: $!\n" unless $sock;
	
	# sending HTTP 1.1 request
	print $sock "GET http://$server:$port$page HTTP/1.1\nHost: $server:$port\nConnection: Closed\n\n";
	
	do{
	  $line = <$sock>
	} until ($line =~ /^\r\n/);
	@webpage = <$sock>;
	close($sock);
	return @webpage;
}

die("Usage:\n\tgetpage server[:port] [page]\n") unless $#ARGV>-1;
print GetHTTPHeader($ARGV[0], $ARGV[1]);
print GetWebPage($ARGV[0], $ARGV[1]);