16.2 Net::FTP (Perl in a Nutshell)

16.2 Net::FTP

Net::FTP is used to transfer files from remote hosts. Using Net::FTP, you can write simple FTP clients that transfer files from remote servers based on information passed on the command line or from hard-coded variables. Here is an example of a client that connects to a remote FTP server and gets a file from the server:

#!/usr/local/bin/perl -w  use Net::FTP;  $hostname = 'remotehost.com'; $username = 'anonymous'; $password = '[email protected]';  # Hardcode the directory and filename to get $home = '/pub'; $filename = 'TESTFILE';  # Open the connection to the host $ftp = Net::FTP->new($hostname);         # construct object $ftp->login($username, $password);       # log in  $ftp->cwd($home),"\n";                   # change directory print $ftp->ls($home),"\n";          # Now get the file and leave $ftp->get($filename);  $ftp->quit;

FTP clients have also been integrated with most World Wide Web browsers, using ftp:// in place of http://. When the URL points to a directory, the browser displays a listing of the directory, where each filename is a link to that file. When the URL points directly to a file, the remote file is downloaded.

Here's an example that uses Net::FTP to list files from a remote FTP server on a web page, with a link from each file to the URL of the file on the remote site:

#!/usr/local/bin/perl -w  use Net::FTP;  $hostname = 'remotehost.com';           # ftp host $username = 'anonymous';                # username $password = '[email protected]';      # password $home = '/pub';  $ftp = Net::FTP->new($hostname);        # Net::FTP constructor $ftp->login($username, $password);      # log in w/username and password  $pwd = $ftp->pwd;                       # get current directory  # Now, output HTML page. print <<HTML; Content-type: text/html <HTML>      <HEAD>     <TITLE>Download Files</TITLE>   </HEAD>   <BODY>              <B>Current working directory:</B> $pwd<BR>       Files to download: <P> HTML        @entries = $ftp->ls($home);       # slurp all entries into an array     foreach (@entries) { # now, output links for all files in the ftp area                          # as links         print "<INPUT TYPE=hidden NAME=\"files\" VALUE=\"$_\">\n";         print "<A HREF=\"ftp://$hostname$_\">",         "<IMG SRC=\"http://www/icons/f.gif\" border=0>\n";         print " $_</A><BR>\n";     }     print <<HTML;   </BODY> </HTML> HTML $ftp->quit;             # end FTP session

The Net::FTP module implements a subset (as shown earlier in this chapter) of the FTP protocol as defined in RFC 959. In addition to providing the methods shown below, the module inherits from Net::Cmd. Some of the Net::FTP methods return an object derived from the dataconn class (which is in turn derived from the IO::Socket::INET class), as noted in the entries for those methods.

The following methods are defined by Net::FTP:


16.1 The FTP Protocol		16.3 FTP Configuration with Net::Netrc