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";
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
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";
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 port number (the default is 21, the standard port for FTP). Finally, if the
Passive option is set to true, all transfers are done passively (some firewalls and proxies require this). The
Passive options override the environment variables
Having connected, the next step is to authenticate. Normally, you'll want to call
login with up to three arguments: username, password, and account.
login()or die "Couldn't authenticate.\n"; $ftp->login($username) or die "Still couldn't authenticate.\n"; $ftp->login($username, $password) or die "Couldn't authenticate, even with explicit username and password.\n"; $ftp->login($username, $password, $account) or die "No dice. It hates me.\n";
If you call
login with no arguments, Net::FTP uses the Net::Netrc module to find settings for the host you've connected to. If none are found there, anonymous login is attempted (username
username@hostname). If no password is given and the username
anonymous is used, the user's mail address is supplied as the password. The optional account argument is not used on most systems. If the authentication fails,
Once authenticated, the usual FTP commands are available as methods called on your Net::FTP object. The
put methods fetch and send files. To send a file, use:
$ftp->put($localfile, $remotefile) or die "Can't send $localfile: $!\n";
If you omit the second argument, the remote file will have the same name as the local file. You can also send from a filehandle (in which case the remote filename must be given as the second argument):
$ftp->put(*STDIN, $remotefile) or die "Can't send from STDIN: $!\n";
If the transfer is interrupted, the remote file is not automatically deleted. The
put method returns the remote filename if it succeeded, or
undef if an error occurred.
To fetch a file, use the
get method, which returns the local filename, or
undef if there was an error:
$ftp->get($remotefile, $localfile) or die "Can't fetch $remotefile : $!\n";
You can also
get into a filehandle, in which case the filehandle is returned (or
undef if there was an error):
$ftp->get($remotefile, *STDOUT) or die "Can't fetch $remotefile: $!\n";
get an optional third argument, an offset into the remote file, to begin the transfer at that offset. Received bytes are appended to the local file.
type method changes the file translation mode. Pass it a string (
"L") and it will return the previous translation mode. The
byte methods call
type with the appropriate string. If an error occurs (the FTP server does not do EBCDIC, for example),
type and its helper methods return
pwd to set and fetch the current remote directory. They both return true if successful, false otherwise. If you
cdup method is called to change the directory to the parent of the current directory. Call
cwd without an argument to change to the root directory.
$ftp->cwd("/pub/perl/CPAN/images/g-rated"); print "I'm in the directory ", $ftp->pwd(), "\n";
rmdir($remotedir) make and delete directories on the remote machine. You have the built-in
rmdir functions to make and delete directories on the local machine. To create all directories up to the given directory, pass a true second argument to
mkdir. For instance, if you want to make /pub, /pub/gnat, and /pub/gnat/perl, say:
$ftp->mkdir("/pub/gnat/perl", 1) or die "Can't create /pub/gnat/perl recursively: $!\n";
mkdir succeeds, the full path to the newly created directory is returned. If it fails,
dir methods get a list of files in a remote directory. Traditionally,
dir gives you a more verbose listing than
ls, but neither has a standard format. Most Unix FTP servers return the output of ls and ls -l respectively, but you can't guarantee that behavior from every FTP server. These methods, in list context, return the list of lines returned by the server. In scalar context, they return a reference to an array.
@lines = $ftp->ls("/pub/gnat/perl") or die "Can't get a list of files in /pub/gnat/perl: $!"; $ref_to_lines = $ftp->dir("/pub/perl/CPAN/src/latest.tar.gz") or die "Can't check status of latest.tar.gz: $!\n";
When you're done and want to close up gracefully, use the
$ftp->quit() or warn "Couldn't quit. Oh well.\n";
Other methods rename, change ownership and permissions of remote files, check the size of the remote file, and so on. Read the Net::FTP documentation for details.
If you want to mirror files between machines, use the excellent mirror program written in Perl by Lee McLoughlin. Look for it on the Web at http://sunsite.doc.ic.ac.uk/packages/mirror/.