Perl Cookbook

Being an FTP Client

Problem

You want to connect to an FTP server and get or put files. You might want to automate the one-time transfer of many files or automatically mirror an entire section of an FTP server, for example.

Solution

Use the CPAN module Net::FTP:

use Net::FTP;

$ftp = Net::FTP->new("ftp.host.com")    or die "Can't connect: $@\n";
$ftp->login($username, $password)       or die "Couldn't login\n";
$ftp->cwd($directory)                   or die "Couldn't change directory\n";
$ftp->get($filename)                    or die "Couldn't get $filename\n";
$ftp->put($filename)                    or die "Couldn't put $filename\n";

Discussion

Using the Net::FTP module is a three-part process: connect to a server, identify and authenticate yourself, and transfer files. All interaction with the FTP server happens through method calls on a Net::FTP object. If an error occurs, methods return undef in scalar context or an empty list in list context.

The connection is established with the new constructor. If an error occurs, $@ is set to an error message and new returns undef. The first argument is the hostname of the FTP server and is optionally followed by named options:

$ftp = Net::FTP->new("ftp.host.com",
                     Timeout => 30,
                     Debug   => 1)
    or die "Can't connect: $@\n";

The Timeout option gives the number of seconds all operations wait before giving up. Debug sets the debugging level (non-zero sends copies of all commands to STDERR). Firewall takes a string as an argument, specifying the machine acting as an FTP proxy. Port lets you specify an alternate ...