Net::FTP - FTP Client class |
Net::FTP - FTP Client class
use Net::FTP;
$ftp = Net::FTP->new("some.host.name", Debug => 0); $ftp->login("anonymous",'-anonymous@'); $ftp->cwd("/pub"); $ftp->get("that.file"); $ftp->quit;
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.
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 local file (on the client) and a
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 /path/to/file
will try to put
that file in /path/to/file
locally, unless you specify a local file
name.
The protocol also defines several standard 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).
HOST
is the
name of the remote host to which an FTP connection is required.
OPTIONS
are passed in a hash like fashion, using key and value pairs.
Possible options are:
Firewall - The name of a machine which acts as an FTP firewall. This can be
overridden by an environment variable 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 @hostname
is
appended to the login identifier. This kind of setup is also refered to
as an ftp proxy.
FirewallType - The type of firewall running on the machine indicated by
Firewall. This can be overridden by an environment variable
FTP_FIREWALL_TYPE
. For a list of permissible types, see the description of
ftp_firewall_type in the Net::Config manpage.
BlockSize - This is the block size that Net::FTP will use when doing transfers. (defaults to 10240)
Port - The port number to connect to on the remote machine for the FTP connection
Timeout - Set a timeout value (defaults to 120)
Debug - debug level (see the debug method in the Net::Cmd manpage)
Passive - If set to a non-zero value then all data transfers will be done
using passive mode. This is not usually required except for some dumb
servers, and some firewall configurations. This can also be set by the
environment variable FTP_PASSIVE
.
Hash - If given a reference to a file handle (e.g., \*STDERR
),
print hash marks (#) on that filehandle every 1024 bytes. This
simply invokes the hash()
method for you, so that hash marks
are displayed for all transfers. You can, of course, call hash()
explicitly whenever you'd like.
If the constructor fails undef will be returned and an error message will be in $@
Unless otherwise stated all methods return either a true or false value, with true meaning that the operation was a success. When a method states that it returns a value, failure will be returned as undef or an empty list.
Net::FTP
uses the Net::Netrc
package to lookup the login information for the connected host.
If no information is found then a login of anonymous is used.
If no password is given and the login is anonymous then anonymous@
will be used for password.
If the connection is via a firewall then the authorize
method will
be called with no arguments.
authorize
uses Net::Netrc
to do a lookup.
Returns most significant digit of the response code.
binary([ARGS])
ebcdic([ARGS])
byte([ARGS])
type
with the first arguments set correctly
NOTE ebcdic and byte are not fully supported.
OLDNAME
to NEWNAME
. This
is done by sending the RNFR and RNTO commands.
FILENAME
.
$dir
. If
$dir
is ".."
, the FTP 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.
DIR
.
DIR
. If RECURSE
is true then
mkdir
will attempt to create all the directories in the given path.
Returns the full pathname to the new directory.
DIR
, or the current directory.
In an array context, returns a list of lines returned from the server. In a scalar context, returns a reference to a list.
DIR
, or the current directory in long format.
In an array context, returns a list of lines returned from the server. In a scalar context, returns a reference to a list.
REMOTE_FILE
from the server and store locally. LOCAL_FILE
may be
a filename or a filehandle. If not specified, the file will be stored in
the current directory with the same leafname as the remote file.
If WHERE
is given then the first WHERE
bytes of the file will
not be transfered, and the remaining bytes will be appended to
the local file if it already exists.
Returns LOCAL_FILE
, or the generated local file name if LOCAL_FILE
is not given. If an error was encountered undef is returned.
LOCAL_FILE
may be a name or a filehandle.
If LOCAL_FILE
is a filehandle then REMOTE_FILE
must be specified. If
REMOTE_FILE
is not specified then the file will be stored in the current
directory with the same leafname as LOCAL_FILE
.
Returns REMOTE_FILE
, or the generated remote filename if REMOTE_FILE
is not given.
NOTE: If for some reason the transfer does not complete and an error is returned then the contents that had been transfered will not be remove automatically.
STOU
command.
Returns the name of the file on the server.
Returns REMOTE_FILE
, or the generated remote filename if REMOTE_FILE
is not given.
STOU
command.
NOTE: The size reported is the size of the stored file on the remote server. If the file is subsequently transfered from the server in ASCII mode and the remote server and local machine have different ideas about ``End Of Line'' then the size of file on the local machine after transfer may be different.
The following methods can return different results depending on
how they are called. If the user explicitly calls either
of the pasv
or port
methods then these methods will
return a true or false value. If the user does not
call either of these methods then the result will be a
reference to a Net::FTP::dataconn
based object.
NLST
command to the server, with an optional parameter.
nlst
but using the LIST
command
FILE
from the remote server.
FILE
is the
name of the new file that should be created.
stor
but using the STOU
command. The name of the unique
file which was created on the server will be available via the unique_name
method after the data connection has been closed.
FILE
. If this file does not exist then create it.
If for some reason you want to have complete control over the data connection,
this includes generating it and calling the 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 get
, put
,
put_unique
and those that do not require data connections.
PORT
command to the server. If PORT
is specified then it is sent
to the server. If not, then a listen socket is created and the correct information
sent to the server.
port
method.
The following methods can be used to transfer files between two remote servers, providing that these two servers can connect directly to each other.
DEST_FILE
is omitted then the leaf name of SRC_FILE
will be used.
pasv_xfer
but the file is stored on the remote server using
the STOU command.
Net::FTP
object for the non-passive server passed as an
argument.
Net::FTP
inherits from Net::Cmd
so methods defined in Net::Cmd
may
be used to send commands to the remote FTP server.
Returns most significant digit of the response code.
WARNING This call should only be used on commands that do not require data connections. Misuse of this method can hang the connection.
Some of the methods defined in Net::FTP
return an object which will
be derived from this class.The dataconn class itself is derived from
the 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.
SIZE
bytes of data from the server and place it into BUFFER
, also
performing any <CRLF> translation necessary. TIMEOUT
is optional, if not
given, the timeout value from the command connection will be used.
Returns the number of bytes read before any <CRLF> translation.
SIZE
bytes of data from BUFFER
to the server, also
performing any <CRLF> translation necessary. TIMEOUT
is optional, if not
given, the timeout value from the command connection will be used.
Returns the number of bytes written before any <CRLF> translation.
The following RFC959 commands have not been implemented:
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 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.
Graham Barr <gbarr@pobox.com>
the Net::Netrc manpage the Net::Cmd manpage
ftp(1), ftpd(8), RFC 959 http://www.cis.ohio-state.edu/htbin/rfc/rfc959.html
For an example of the use of Net::FTP see
autoftp
is a program that can retrieve, send, or list files via
the FTP protocol in a non-interactive manner.
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
Copyright (c) 1995-1998 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.
$Id: //depot/libnet/Net/FTP.pm#68 $
Net::FTP - FTP Client class |