# Net::FTP.pm## Copyright (c) 1995 Graham Barr <gbarr@ti.com>. All rights reserved.# This program is free software; you can redistribute it and/or# modify it under the same terms as Perl itself.## Documentation (at end) improved 1996 by Nathan Torkington <gnat@frii.com>.package Net::FTP;require 5.001;use strict;use vars qw(@ISA $VERSION);use Carp;use Socket 1.3;use IO::Socket;use Time::Local;use Net::Cmd;use Net::Config;$VERSION = do { my @r=(q$Revision: 1.1 $=~/\d+/g); sprintf "%d."."%02d"x$#r,@r};@ISA     = qw(Exporter Net::Cmd IO::Socket::INET);sub new{ my $pkg  = shift; my $peer = shift; my %arg  = @_;  my $host = $peer; my $fire = undef; unless(defined inet_aton($peer)) # GMB: Should I use Net::Ping here ??  {   $fire = $ENV{FTP_FIREWALL}	|| $arg{Firewall}	|| $NetConfig{ftp_firewall}	|| undef;   if(defined $fire)    {     $peer = $fire;     delete $arg{Port};    }  } my $ftp = $pkg->SUPER::new(PeerAddr => $peer, 			    PeerPort => $arg{Port} || 'ftp(21)',			    Proto    => 'tcp',			    Timeout  => defined $arg{Timeout}						? $arg{Timeout}						: 120			   ) or return undef; ${*$ftp}{'net_ftp_host'}     = $host;		# Remote hostname ${*$ftp}{'net_ftp_type'}     = 'A';		# ASCII/binary/etc mode ${*$ftp}{'net_ftp_firewall'} = $fire	if(defined $fire); ${*$ftp}{'net_ftp_passive'} = int	exists $arg{Passive}	    ? $arg{Passive}	    : exists $ENV{FTP_PASSIVE}		? $ENV{FTP_PASSIVE}		: defined $fire		    ? $NetConfig{ftp_ext_passive}		    : $NetConfig{ftp_int_passive};	# Whew! :-) $ftp->autoflush(1); $ftp->debug(exists $arg{Debug} ? $arg{Debug} : undef); unless ($ftp->response() == CMD_OK)  {   $ftp->SUPER::close();   undef $ftp;  } $ftp;}#### User interface methods##sub quit{ my $ftp = shift; $ftp->_QUIT    && $ftp->close;}sub close{ my $ftp = shift; ref($ftp)     && defined fileno($ftp)    && $ftp->SUPER::close;}sub DESTROY { shift->close }sub ascii  { shift->type('A',@_); }sub binary { shift->type('I',@_); }sub ebcdic{ carp "TYPE E is unsupported, shall default to I"; shift->type('E',@_);}sub byte{ carp "TYPE L is unsupported, shall default to I"; shift->type('L',@_);}# Allow the user to send a command directly, BE CAREFUL !!sub quot{  my $ftp = shift; my $cmd = shift; $ftp->command( uc $cmd, @_); $ftp->response();}sub mdtm{ my $ftp  = shift; my $file = shift; $ftp->_MDTM($file) && $ftp->message =~ /(\d{4})(\d\d)(\d\d)(\d\d)(\d\d)(\d\d)/    ? timegm($6,$5,$4,$3,$2-1,$1 - 1900)    : undef;}sub size{ my $ftp  = shift; my $file = shift; $ftp->_SIZE($file)	? ($ftp->message =~ /(\d+)/)[0]	: undef;}sub login{ my($ftp,$user,$pass,$acct) = @_; my($ok,$ruser); unless (defined $user)  {   require Net::Netrc;   my $rc = Net::Netrc->lookup(${*$ftp}{'net_ftp_host'});   ($user,$pass,$acct) = $rc->lpa()	if ($rc);  } $user ||= "anonymous"; $ruser = $user; if(defined ${*$ftp}{'net_ftp_firewall'})  {   $user .= "@" . ${*$ftp}{'net_ftp_host'};  } $ok = $ftp->_USER($user); # Some dumb firewall's don't prefix the connection messages $ok = $ftp->response()	if($ok == CMD_OK && $ftp->code == 220 && $user =~ /\@/); if ($ok == CMD_MORE)  {   unless(defined $pass)    {     require Net::Netrc;     my $rc = Net::Netrc->lookup(${*$ftp}{'net_ftp_host'}, $ruser);     ($ruser,$pass,$acct) = $rc->lpa()	if ($rc);     $pass = "-" . (getpwuid($>))[0] . "@"         if (!defined $pass && $ruser =~ /^anonymous/o);    }   $ok = $ftp->_PASS($pass || "");  } $ok = $ftp->_ACCT($acct || "")	if ($ok == CMD_MORE); $ftp->authorize()    if($ok == CMD_OK && defined ${*$ftp}{'net_ftp_firewall'}); $ok == CMD_OK;}sub authorize{ @_ >= 1 || @_ <= 3 or croak 'usage: $ftp->authorize( [AUTH [, RESP]])'; my($ftp,$auth,$resp) = @_; unless(defined $resp)  {   require Net::Netrc;   $auth ||= (getpwuid($>))[0];   my $rc = Net::Netrc->lookup(${*$ftp}{'net_ftp_firewall'}, $auth)        || Net::Netrc->lookup(${*$ftp}{'net_ftp_firewall'});   ($auth,$resp) = $rc->lpa()     if($rc);  } my $ok = $ftp->_AUTH($auth || ""); $ok = $ftp->_RESP($resp || "")	if ($ok == CMD_MORE); $ok == CMD_OK;}sub rename{ @_ == 3 or croak 'usage: $ftp->rename(FROM, TO)'; my($ftp,$from,$to) = @_; $ftp->_RNFR($from)    && $ftp->_RNTO($to);}sub type{ my $ftp = shift; my $type = shift; my $oldval = ${*$ftp}{'net_ftp_type'}; return $oldval	unless (defined $type); return undef	unless ($ftp->_TYPE($type,@_)); ${*$ftp}{'net_ftp_type'} = join(" ",$type,@_); $oldval;}my($TELNET_IAC,$TELNET_IP,$TELNET_DM) = (255,244,242);sub abort{ my $ftp = shift; send($ftp,pack("CC",$TELNET_IAC,$TELNET_IP),0); send($ftp,pack("C", $TELNET_IAC),MSG_OOB); send($ftp,pack("C", $TELNET_DM),0); $ftp->command("ABOR"); defined ${*$ftp}{'net_ftp_dataconn'}    ? ${*$ftp}{'net_ftp_dataconn'}->close()    : $ftp->response(); $ftp->response()    if $ftp->status == CMD_REJECT; $ftp->status == CMD_OK;}sub get{ my($ftp,$remote,$local,$where) = @_; my($loc,$len,$buf,$resp,$localfd,$data); local *FD; $localfd = ref($local) ? fileno($local)			: undef; ($local = $remote) =~ s#^.*/##	unless(defined $local); ${*$ftp}{'net_ftp_rest'} = $where	if ($where); delete ${*$ftp}{'net_ftp_port'}; delete ${*$ftp}{'net_ftp_pasv'}; $data = $ftp->retr($remote) or	return undef; if(defined $localfd)  {   $loc = $local;  } else  {   $loc = \*FD;   unless(($where) ? open($loc,">>$local") : open($loc,">$local"))    {     carp "Cannot open Local file $local: $!\n";     $data->abort;     return undef;    }  } if(($ftp->type =~ /^I/) && !binmode($loc))  {   carp "Cannot binmode Local file $local: $!\n";   $data->abort;   return undef;  } $buf = ''; do  {   $len = $data->read($buf,1024);  } while($len > 0 && syswrite($loc,$buf,$len) == $len); close($loc)	unless defined $localfd;  $data->close(); # implied $ftp->response return $local;}sub cwd{ @_ == 2 || @_ == 3 or croak 'usage: $ftp->cwd( [ DIR ] )'; my($ftp,$dir) = @_; $dir ||= "/"; $dir eq ".."    ? $ftp->_CDUP()    : $ftp->_CWD($dir);}sub cdup{ @_ == 1 or croak 'usage: $ftp->cdup()'; $_[0]->_CDUP;}sub pwd{ @_ == 1 || croak 'usage: $ftp->pwd()'; my $ftp = shift; $ftp->_PWD(); $ftp->_extract_path;}sub rmdir{ @_ == 2 || croak 'usage: $ftp->rmdir( DIR )'; $_[0]->_RMD($_[1]);}sub mkdir{ @_ == 2 || @_ == 3 or croak 'usage: $ftp->mkdir( DIR [, RECURSE ] )'; my($ftp,$dir,$recurse) = @_; $ftp->_MKD($dir) || $recurse or    return undef; my $path = $dir; unless($ftp->ok)  {   my @path = split(m#(?=/+)#, $dir);   $path = "";   while(@path)    {     $path .= shift @path;     $ftp->_MKD($path);     $path = $ftp->_extract_path($path);     # 521 means directory already exists     last        unless $ftp->ok || $ftp->code == 521 || $ftp->code == 550;    }  } $ftp->_extract_path($path);}sub delete{ @_ == 2 || croak 'usage: $ftp->delete( FILENAME )'; $_[0]->_DELE($_[1]);}sub put        { shift->_store_cmd("stor",@_) }sub put_unique { shift->_store_cmd("stou",@_) }sub append     { shift->_store_cmd("appe",@_) }sub nlst { shift->_data_cmd("NLST",@_) }sub list { shift->_data_cmd("LIST",@_) }sub retr { shift->_data_cmd("RETR",@_) }sub stor { shift->_data_cmd("STOR",@_) }sub stou { shift->_data_cmd("STOU",@_) }sub appe { shift->_data_cmd("APPE",@_) }sub _store_cmd { my($ftp,$cmd,$local,$remote) = @_; my($loc,$sock,$len,$buf,$localfd); local *FD; use File::Basename; $localfd = ref($local) ? fileno($local)			: undef; unless(defined $remote)  {   croak 'Must specify remote filename with stream input'	if defined $localfd;#  ($remote = $local) =~ s%.*/%%;   $remote = basename($local);  } if(defined $localfd)  {   $loc = $local;  } else  {   $loc = \*FD;   unless(open($loc,"<$local"))    {     carp "Cannot open Local file $local: $!\n";     return undef;    }  } if(($ftp->type =~ /^I/) && !binmode($loc))  {   carp "Cannot binmode Local file $local: $!\n";   return undef;  } delete ${*$ftp}{'net_ftp_port'}; delete ${*$ftp}{'net_ftp_pasv'}; $sock = $ftp->_data_cmd($cmd, $remote) or 	return undef; while(1)  {   last unless $len = sysread($loc,$buf="",1024);   unless($sock->write($buf,$len) == $len)    {     $sock->abort;     close($loc)	unless defined $localfd;     return undef;    }  } $sock->close(); close($loc)	unless defined $localfd; ($remote) = $ftp->message =~ /unique file name:\s*(\S*)\s*\)/	if ('STOU' eq uc $cmd); return $remote;}sub port{ @_ == 1 || @_ == 2 or croak 'usage: $ftp->port([PORT])'; my($ftp,$port) = @_; my $ok; delete ${*$ftp}{'net_ftp_intern_port'}; unless(defined $port)  {   # create a Listen socket at same address as the command socket   ${*$ftp}{'net_ftp_listen'} ||= IO::Socket::INET->new(Listen    => 5,				    	    	        Proto     => 'tcp',				    	    	        LocalAddr => $ftp->sockhost, 				    	    	       );     my $listen = ${*$ftp}{'net_ftp_listen'};   my($myport, @myaddr) = ($listen->sockport, split(/\./,$listen->sockhost));   $port = join(',', @myaddr, $myport >> 8, $myport & 0xff);   ${*$ftp}{'net_ftp_intern_port'} = 1;  } $ok = $ftp->_PORT($port); ${*$ftp}{'net_ftp_port'} = $port; $ok;}sub ls  { shift->_list_cmd("NLST",@_); }sub dir { shift->_list_cmd("LIST",@_); }sub pasv{ @_ == 1 or croak 'usage: $ftp->pasv()'; my $ftp = shift; delete ${*$ftp}{'net_ftp_intern_port'}; $ftp->_PASV && $ftp->message =~ /(\d+(,\d+)+)/    ? ${*$ftp}{'net_ftp_pasv'} = $1    : undef;    }sub unique_name{ my $ftp = shift; ${*$ftp}{'net_ftp_unique'} || undef;}#### Depreciated methods##sub lsl{ carp "Use of Net::FTP::lsl depreciated, use 'dir'"    if $^W; goto &dir;}sub authorise{ carp "Use of Net::FTP::authorise depreciated, use 'authorize'"    if $^W; goto &authorize;}#### Private methods##sub _extract_path{ my($ftp, $path) = @_; # This tries to work both with and without the quote doubling # convention (RFC 959 requires it, but the first 3 servers I checked # didn't implement it).  It will fail on a server which uses a quote in # the message which isn't a part of or surrounding the path. $ftp->ok &&    $ftp->message =~ /(?:^|\s)\"(.*)\"(?:$|\s)/ &&    ($path = $1) =~ s/\"\"/\"/g; $path;}#### Communication methods##sub _dataconn{ my $ftp = shift; my $data = undef; my $pkg = "Net::FTP::" . $ftp->type; $pkg =~ s/ /_/g; delete ${*$ftp}{'net_ftp_dataconn'}; if(defined ${*$ftp}{'net_ftp_pasv'})  {   my @port = split(/,/,${*$ftp}{'net_ftp_pasv'});   $data = $pkg->new(PeerAddr => join(".",@port[0..3]),    	    	     PeerPort => $port[4] * 256 + $port[5],    	    	     Proto    => 'tcp'    	    	    );  } elsif(defined ${*$ftp}{'net_ftp_listen'})  {   $data = ${*$ftp}{'net_ftp_listen'}->accept($pkg);   close(delete ${*$ftp}{'net_ftp_listen'});  } if($data)  {   ${*$data} = "";   $data->timeout($ftp->timeout);   ${*$ftp}{'net_ftp_dataconn'} = $data;   ${*$data}{'net_ftp_cmd'} = $ftp;  } $data;}sub _list_cmd{ my $ftp = shift; my $cmd = uc shift; delete ${*$ftp}{'net_ftp_port'}; delete ${*$ftp}{'net_ftp_pasv'}; my $data = $ftp->_data_cmd($cmd,@_); return undef	unless(defined $data); bless $data, "Net::FTP::A"; # Force ASCII mode my $databuf = ''; my $buf = ''; while($data->read($databuf,1024))  {   $buf .= $databuf;  } my $list = [ split(/\n/,$buf) ]; $data->close(); wantarray ? @{$list}           : $list;}sub _data_cmd{ my $ftp = shift; my $cmd = uc shift; my $ok = 1; my $where = delete ${*$ftp}{'net_ftp_rest'} || 0; if(${*$ftp}{'net_ftp_passive'} &&     !defined ${*$ftp}{'net_ftp_pasv'} &&     !defined ${*$ftp}{'net_ftp_port'})  {   my $data = undef;   $ok = defined $ftp->pasv;   $ok = $ftp->_REST($where)	if $ok && $where;   if($ok)    {     $ftp->command($cmd,@_);     $data = $ftp->_dataconn();     $ok = CMD_INFO == $ftp->response();      return $data        if $ok;      $data->_close        if $data;    }    return undef;  } $ok = $ftp->port    unless (defined ${*$ftp}{'net_ftp_port'} ||            defined ${*$ftp}{'net_ftp_pasv'}); $ok = $ftp->_REST($where)    if $ok && $where; return undef    unless $ok; $ftp->command($cmd,@_); return 1    if(defined ${*$ftp}{'net_ftp_pasv'}); $ok = CMD_INFO == $ftp->response(); return $ok     unless exists ${*$ftp}{'net_ftp_intern_port'}; return $ftp->_dataconn()	if $ok; close(delete ${*$ftp}{'net_ftp_listen'});  return undef;}#### Over-ride methods (Net::Cmd)##sub debug_text { $_[2] =~ /^(pass|resp)/i ? "$1 ....\n" : $_[2]; }sub command{ my $ftp = shift; delete ${*$ftp}{'net_ftp_port'}; $ftp->SUPER::command(@_);}sub response{ my $ftp = shift; my $code = $ftp->SUPER::response(); delete ${*$ftp}{'net_ftp_pasv'}    if ($code != CMD_MORE && $code != CMD_INFO); $code;}sub parse_response{ return ($1, $2 eq "-")    if $_[1] =~ s/^(\d\d\d)(.?)//o; my $ftp = shift; # Darn MS FTP server is a load of CRAP !!!! return ()	unless ${*$ftp}{'net_cmd_code'}; (${*$ftp}{'net_cmd_code'},1);}#### Allow 2 servers to talk directly##sub pasv_xfer{ my($sftp,$sfile,$dftp,$dfile) = @_; ($dfile = $sfile) =~ s#.*/##    unless(defined $dfile); my $port = $sftp->pasv or    return undef; unless($dftp->port($port) && $sftp->retr($sfile) && $dftp->stou($dfile))  {   $sftp->abort;   $dftp->abort;   return undef;  } $dftp->pasv_wait($sftp);}sub pasv_wait{ @_ == 2 or croak 'usage: $ftp->pasv_wait(NON_PASV_FTP)'; my($ftp, $non_pasv) = @_; my($file,$rin,$rout); vec($rin,fileno($ftp),1) = 1; select($rout=$rin, undef, undef, undef); $ftp->response(); $non_pasv->response(); return undef	unless $ftp->ok() && $non_pasv->ok(); return $1	if $ftp->message =~ /unique file name:\s*(\S*)\s*\)/; return $1	if $non_pasv->message =~ /unique file name:\s*(\S*)\s*\)/; return 1;}sub cmd { shift->command(@_)->responce() }########################################## RFC959 commands#sub _ABOR { shift->command("ABOR")->response()	 == CMD_OK }sub _CDUP { shift->command("CDUP")->response()	 == CMD_OK }sub _NOOP { shift->command("NOOP")->response()	 == CMD_OK }sub _PASV { shift->command("PASV")->response()	 == CMD_OK }sub _QUIT { shift->command("QUIT")->response()	 == CMD_OK }sub _DELE { shift->command("DELE",@_)->response() == CMD_OK }sub _CWD  { shift->command("CWD", @_)->response() == CMD_OK }sub _PORT { shift->command("PORT",@_)->response() == CMD_OK }sub _RMD  { shift->command("RMD", @_)->response() == CMD_OK }sub _MKD  { shift->command("MKD", @_)->response() == CMD_OK }sub _PWD  { shift->command("PWD", @_)->response() == CMD_OK }sub _TYPE { shift->command("TYPE",@_)->response() == CMD_OK }sub _RNTO { shift->command("RNTO",@_)->response() == CMD_OK }sub _ACCT { shift->command("ACCT",@_)->response() == CMD_OK }sub _RESP { shift->command("RESP",@_)->response() == CMD_OK }sub _MDTM { shift->command("MDTM",@_)->response() == CMD_OK }sub _SIZE { shift->command("SIZE",@_)->response() == CMD_OK }sub _APPE { shift->command("APPE",@_)->response() == CMD_INFO }sub _LIST { shift->command("LIST",@_)->response() == CMD_INFO }sub _NLST { shift->command("NLST",@_)->response() == CMD_INFO }sub _RETR { shift->command("RETR",@_)->response() == CMD_INFO }sub _STOR { shift->command("STOR",@_)->response() == CMD_INFO }sub _STOU { shift->command("STOU",@_)->response() == CMD_INFO }sub _RNFR { shift->command("RNFR",@_)->response() == CMD_MORE }sub _REST { shift->command("REST",@_)->response() == CMD_MORE }sub _USER { shift->command("user",@_)->response() } # A certain brain dead firewall :-)sub _PASS { shift->command("PASS",@_)->response() }sub _AUTH { shift->command("AUTH",@_)->response() }sub _ALLO { shift->unsupported(@_) }sub _SMNT { shift->unsupported(@_) }sub _HELP { shift->unsupported(@_) }sub _MODE { shift->unsupported(@_) }sub _SITE { shift->unsupported(@_) }sub _SYST { shift->unsupported(@_) }sub _STAT { shift->unsupported(@_) }sub _STRU { shift->unsupported(@_) }sub _REIN { shift->unsupported(@_) }#### Generic data connection package##package Net::FTP::dataconn;use Carp;use vars qw(@ISA $timeout);use Net::Cmd;@ISA = qw(IO::Socket::INET);sub abort{ my $data = shift; my $ftp  = ${*$data}{'net_ftp_cmd'}; $ftp->abort; # this will close me}sub _close{ my $data = shift; my $ftp  = ${*$data}{'net_ftp_cmd'}; $data->SUPER::close(); delete ${*$ftp}{'net_ftp_dataconn'}    if exists ${*$ftp}{'net_ftp_dataconn'} &&        $data == ${*$ftp}{'net_ftp_dataconn'};}sub close{ my $data = shift; my $ftp  = ${*$data}{'net_ftp_cmd'}; $data->_close; $ftp->response() == CMD_OK &&    $ftp->message =~ /unique file name:\s*(\S*)\s*\)/ &&    (${*$ftp}{'net_ftp_unique'} = $1); $ftp->status == CMD_OK;}sub _select{ my    $data 	= shift; local *timeout = \$_[0]; shift; my    $rw 	= shift; my($rin,$win); return 1 unless $timeout; $rin = ''; vec($rin,fileno($data),1) = 1; $win = $rw ? undef : $rin; $rin = undef unless $rw; my $nfound = select($rin, $win, undef, $timeout); croak "select: $!"	if $nfound < 0; return $nfound;}sub can_read{ my    $data    = shift; local *timeout = \$_[0]; $data->_select($timeout,1);}sub can_write{ my    $data    = shift; local *timeout = \$_[0]; $data->_select($timeout,0);}sub cmd{ my $ftp = shift; ${*$ftp}{'net_ftp_cmd'};}@Net::FTP::L::ISA = qw(Net::FTP::I);@Net::FTP::E::ISA = qw(Net::FTP::I);#### Package to read/write on ASCII data connections##package Net::FTP::A;use vars qw(@ISA $buf);use Carp;@ISA = qw(Net::FTP::dataconn);sub read{ my    $data 	= shift; local *buf 	= \$_[0]; shift; my    $size 	= shift || croak 'read($buf,$size,[$offset])'; my    $offset 	= shift || 0; my    $timeout = $data->timeout; croak "Bad offset"	if($offset < 0); $offset = length $buf	if($offset > length $buf); ${*$data} ||= ""; my $l = 0; READ:  {   $data->can_read($timeout) or	croak "Timeout";   my $n = sysread($data, ${*$data}, $size, length ${*$data});   return $n	unless($n >= 0);   ${*$data} =~ s/(\015)?(?!\012)\Z//so;   my $lf = $1 || "";   ${*$data} =~ s/\015\012/\n/sgo;   substr($buf,$offset) = ${*$data};   $l += length(${*$data});   $offset += length(${*$data});   ${*$data} = $lf;      redo READ     if($l == 0 && $n > 0);   if($n == 0 && $l == 0)    {     substr($buf,$offset) = ${*$data};     ${*$data} = "";    }  } return $l;}sub write{ my    $data 	= shift; local *buf 	= \$_[0]; shift; my    $size 	= shift || croak 'write($buf,$size,[$timeout])'; my    $timeout = @_ ? shift : $data->timeout; $data->can_write($timeout) or	croak "Timeout"; # What is previous pkt ended in \015 or not ?? my $tmp;#($tmp = $buf) =~ s/(?!\015)\012/\015\012/sg; ($tmp = $buf) =~ s/\n/\015\012/sg; my $len = $size + length($tmp) - length($buf); my $wrote = syswrite($data, $tmp, $len); if($wrote >= 0)  {   $wrote = $wrote == $len ? $size			   : $len - $wrote  } return $wrote;}#### Package to read/write on BINARY data connections##package Net::FTP::I;use vars qw(@ISA $buf);use Carp;@ISA = qw(Net::FTP::dataconn);sub read{ my    $data 	= shift; local *buf 	= \$_[0]; shift; my    $size    = shift || croak 'read($buf,$size,[$timeout])'; my    $timeout = @_ ? shift : $data->timeout; $data->can_read($timeout) or	croak "Timeout"; my $n = sysread($data, $buf, $size); $n;}sub write{ my    $data    = shift; local *buf     = \$_[0]; shift; my    $size    = shift || croak 'write($buf,$size,[$timeout])'; my    $timeout = @_ ? shift : $data->timeout; $data->can_write($timeout) or	croak "Timeout"; syswrite($data, $buf, $size);}1;__END__=head1 NAMENet::FTP - FTP Client class=head1 SYNOPSIS    use Net::FTP;        $ftp = Net::FTP->new("some.host.name");    $ftp->login("anonymous","me@here.there");    $ftp->cwd("/pub");    $ftp->get("that.file");    $ftp->quit;=head1 DESCRIPTIONC<Net::FTP> is a class implementing a simple FTP client in Perl asdescribed in RFC959.  It provides wrappers for a subset of the RFC959commands.=head1 OVERVIEWFTP stands for File Transfer Protocol.  It is a way of transferringfiles between networked machines.  The protocol defines a client(whose commands are provided by this module) and a server (notimplemented in this module).  Communication is always initiated by theclient, and the server responds with a message and a status code (andsometimes with data).The FTP protocol allows files to be sent to or fetched from theserver.  Each transfer involves a B<local file> (on the client) and aB<remote file> (on the server).  In this module, the same file namewill be used for both local and remote if only one is specified.  Thismeans that transferring remote file C</path/to/file> will try to putthat file in C</path/to/file> locally, unless you specify a local filename.The protocol also defines several standard B<translations> which thefile can undergo during transfer.  These are ASCII, EBCDIC, binary,and byte.  ASCII is the default type, and indicates that the sender offiles will translate the ends of lines to a standard representationwhich the receiver will then translate back into their localrepresentation.  EBCDIC indicates the file being transferred is inEBCDIC format.  Binary (also known as image) format sends the data asa contiguous bit stream.  Byte format transfers the data as bytes, thevalues of which remain the same regardless of differences in byte sizebetween the two machines (in theory - in practice you should only usethis if you really know what you're doing).=head1 CONSTRUCTOR=over 4=item new (HOST [,OPTIONS])This is the constructor for a new Net::FTP object. C<HOST> is thename of the remote host to which a FTP connection is required.C<OPTIONS> are passed in a hash like fashion, using key and value pairs.Possible options are:B<Firewall> - The name of a machine which acts as a FTP firewall. This can beoverridden by an environment variable C<FTP_FIREWALL>. If specified, and thegiven host cannot be directly connected to, then theconnection is made to the firewall machine and the string C<@hostname> isappended to the login identifier. This kind of setup is also refered toas a ftp proxy.B<Port> - The port number to connect to on the remote machine for theFTP connectionB<Timeout> - Set a timeout value (defaults to 120)B<Debug> - debug level (see the debug method in L<Net::Cmd>)B<Passive> - If set to I<true> then all data transfers will be done using passive mode. This is required for some I<dumb> servers, and somefirewall configurations.  This can also be set by the environmentvariable C<FTP_PASSIVE>.=back=head1 METHODSUnless otherwise stated all methods return either a I<true> or I<false>value, with I<true> meaning that the operation was a success. When a methodstates that it returns a value, failure will be returned as I<undef> or anempty list.=over 4=item login ([LOGIN [,PASSWORD [, ACCOUNT] ] ])Log into the remote FTP server with the given login information. Ifno arguments are given then the C<Net::FTP> uses the C<Net::Netrc>package to lookup the login information for the connected host.If no information is found then a login of I<anonymous> is used.If no password is given and the login is I<anonymous> then the usersEmail address will be used for a password.If the connection is via a firewall then the C<authorize> method willbe called with no arguments.=item authorize ( [AUTH [, RESP]])This is a protocol used by some firewall ftp proxies. It is usedto authorise the user to send data out.  If both arguments are not specifiedthen C<authorize> uses C<Net::Netrc> to do a lookup.=item type (TYPE [, ARGS])This method will send the TYPE command to the remote FTP serverto change the type of data transfer. The return value is the previousvalue.=item ascii ([ARGS]) binary([ARGS]) ebcdic([ARGS]) byte([ARGS])Synonyms for C<type> with the first arguments set correctlyB<NOTE> ebcdic and byte are not fully supported.=item rename ( OLDNAME, NEWNAME )Rename a file on the remote FTP server from C<OLDNAME> to C<NEWNAME>. Thisis done by sending the RNFR and RNTO commands.=item delete ( FILENAME )Send a request to the server to delete C<FILENAME>.=item cwd ( [ DIR ] )Attempt to change directory to the directory given in C<$dir>.  IfC<$dir> is C<"..">, the FTP C<CDUP> command is used to attempt tomove up one directory. If no directory is given then an attempt is madeto change the directory to the root directory.=item cdup ()Change directory to the parent of the current directory.=item pwd ()Returns the full pathname of the current directory.=item rmdir ( DIR )Remove the directory with the name C<DIR>.=item mkdir ( DIR [, RECURSE ])Create a new directory with the name C<DIR>. If C<RECURSE> is I<true> thenC<mkdir> will attempt to create all the directories in the given path.Returns the full pathname to the new directory.=item ls ( [ DIR ] )Get a directory listing of C<DIR>, or the current directory.Returns a reference to a list of lines returned from the server.=item dir ( [ DIR ] )Get a directory listing of C<DIR>, or the current directory in long format.Returns a reference to a list of lines returned from the server.=item get ( REMOTE_FILE [, LOCAL_FILE ] )Get C<REMOTE_FILE> from the server and store locally. C<LOCAL_FILE> may bea filename or a filehandle. If not specified the the file will be stored inthe current directory with the same leafname as the remote file.If C<WHERE> is specified, continue transfer of the remote filefrom this point.Returns C<LOCAL_FILE>, or the generated local file name if C<LOCAL_FILE>is not given.=item put ( LOCAL_FILE [, REMOTE_FILE ] )Put a file on the remote server. C<LOCAL_FILE> may be a name or a filehandle.If C<LOCAL_FILE> is a filehandle then C<REMOTE_FILE> must be specified. IfC<REMOTE_FILE> is not specified then the file will be stored in the currentdirectory with the same leafname as C<LOCAL_FILE>.Returns C<REMOTE_FILE>, or the generated remote filename if C<REMOTE_FILE>is not given.=item put_unique ( LOCAL_FILE [, REMOTE_FILE ] )Same as put but uses the C<STOU> command.Returns the name of the file on the server.=item append ( LOCAL_FILE [, REMOTE_FILE ] )Same as put but appends to the file on the remote server.Returns C<REMOTE_FILE>, or the generated remote filename if C<REMOTE_FILE>is not given.=item unique_name ()Returns the name of the last file stored on the server using theC<STOU> command.=item mdtm ( FILE )Returns the I<modification time> of the given file=item size ( FILE )Returns the size in bytes for the given file.=backThe following methods can return different results depending onhow they are called. If the user explicitly calls eitherof the C<pasv> or C<port> methods then these methods willreturn a I<true> or I<false> value. If the user does notcall either of these methods then the result will be areference to a C<Net::FTP::dataconn> based object.=over 4=item nlst ( [ DIR ] )Send a C<NLST> command to the server, with an optional parameter.=item list ( [ DIR ] )Same as C<nlst> but using the C<LIST> command=item retr ( FILE )Begin the retrieval of a file called C<FILE> from the remote server.=item stor ( FILE )Tell the server that you wish to store a file. C<FILE> is thename of the new file that should be created.=item stou ( FILE )Same as C<stor> but using the C<STOU> command. The name of the uniquefile which was created on the server will be available via the C<unique_name>method after the data connection has been closed.=item appe ( FILE )Tell the server that we want to append some data to the end of a filecalled C<FILE>. If this file does not exist then create it.=backIf for some reason you want to have complete control over the data connection,this includes generating it and calling the C<response> method when required,then the user can use these methods to do so.However calling these methods only affects the use of the methods above thatcan return a data connection. They have no effect on methods C<get>, C<put>,C<put_unique> and those that do not require data connections.=over 4=item port ( [ PORT ] )Send a C<PORT> command to the server. If C<PORT> is specified then it is sentto the server. If not the a listen socket is created and the correct informationsent to the server.=item pasv ()Tell the server to go into passive mode. Returns the text that represents theport on which the server is listening, this text is in a suitable form tosent to another ftp server using the C<port> method.=backThe following methods can be used to transfer files between two remoteservers, providing that these two servers can connect directly to each other.=over 4=item pasv_xfer ( SRC_FILE, DEST_SERVER [, DEST_FILE ] )This method will do a file transfer between two remote ftp servers. IfC<DEST_FILE> is omitted then the leaf name of C<SRC_FILE> will be used.=item pasv_wait ( NON_PASV_SERVER )This method can be used to wait for a transfer to complete between a passiveserver and a non-passive server. The method should be called on the passiveserver with the C<Net::FTP> object for the non-passive server passed as anargument.=item abort ()Abort the current data transfer.=item quit ()Send the QUIT command to the remote FTP server and close the socket connection.=back=head2 Methods for the adventurousC<Net::FTP> inherits from C<Net::Cmd> so methods defined in C<Net::Cmd> maybe used to send commands to the remote FTP server.=over 4=item quot (CMD [,ARGS])Send a command, that Net::FTP does not directly support, to the remoteserver and wait for a response.Returns most significant digit of the response code.B<WARNING> This call should only be used on commands that do not requiredata connections. Misuse of this method can hang the connection.=back=head1 THE dataconn CLASSSome of the methods defined in C<Net::FTP> return an object which willbe derived from this class.The dataconn class itself is derived fromthe C<IO::Socket::INET> class, so any normal IO operations can be performed.However the following methods are defined in the dataconn class and IO shouldbe performed using these.=over 4=item read ( BUFFER, SIZE [, TIMEOUT ] )Read C<SIZE> bytes of data from the server and place it into C<BUFFER>, alsoperforming any <CRLF> translation necessary. C<TIMEOUT> is optional, if notgiven the the timeout value from the command connection will be used.Returns the number of bytes read before any <CRLF> translation.=item write ( BUFFER, SIZE [, TIMEOUT ] )Write C<SIZE> bytes of data from C<BUFFER> to the server, alsoperforming any <CRLF> translation necessary. C<TIMEOUT> is optional, if notgiven the the timeout value from the command connection will be used.Returns the number of bytes written before any <CRLF> translation.=item abort ()Abort the current data transfer.=item close ()Close the data connection and get a response from the FTP server. ReturnsI<true> if the connection was closed successfully and the first digit ofthe response from the server was a '2'.=back=head1 UNIMPLEMENTEDThe following RFC959 commands have not been implemented:=over 4=item B<ALLO>Allocates storage for the file to be transferred.=item B<SMNT>Mount a different file system structure without changing login oraccounting information.=item B<HELP>Ask the server for "helpful information" (that's what the RFC says) onthe commands it accepts.=item B<MODE>Specifies transfer mode (stream, block or compressed) for file to betransferred.=item B<SITE>Request remote server site parameters.=item B<SYST>Request remote server system identification.=item B<STAT>Request remote server status.=item B<STRU>Specifies file structure for file to be transferred.=item B<REIN>Reinitialize the connection, flushing all I/O and account information.=back=head1 REPORTING BUGSWhen reporting bugs/problems please include as much information as possible.It may be difficult for me to reproduce the problem as almost every setupis different.A small script which yields the problem will probably be of help. It wouldalso be useful if this script was run with the extra options C<Debug => 1>passed to the constructor, and the output sent with the bug report. If youcannot include a small script then please include a Debug trace from arun of your program which does yield the problem.=head1 AUTHORGraham Barr <gbarr@ti.com>=head1 SEE ALSOL<Net::Netrc>L<Net::Cmd>ftp(1), ftpd(8), RFC 959http://www.cis.ohio-state.edu/htbin/rfc/rfc959.html=head1 CREDITSHenry Gabryjelski <henryg@WPI.EDU> - for the suggestion of creating directoriesrecursively.Nathan Torkington <gnat@frii.com> - for some input on the documentation.Roderick Schertler <roderick@gate.net> - for various inputs=head1 COPYRIGHTCopyright (c) 1995-1997 Graham Barr. All rights reserved.This program is free software; you can redistribute it and/or modify itunder the same terms as Perl itself.=cut