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Net::FTP(3p)     Perl Programmers Reference Guide    Net::FTP(3p)


NAME
       Net::FTP - FTP Client class

SYNOPSIS
           use Net::FTP;

           $ftp = Net::FTP->new("some.host.name", Debug => 0)
             or die "Cannot connect to some.host.name: $@";

           $ftp->login("anonymous",'-anonymous@')
             or die "Cannot login ", $ftp->message;

           $ftp->cwd("/pub")
             or die "Cannot change working directory ", $ftp->message;

           $ftp->get("that.file")
             or die "get failed ", $ftp->message;

           $ftp->quit;

DESCRIPTION
       "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.

OVERVIEW
       FTP stands for File Transfer Protocol.  It is a way of
       transferring files between networked machines.  The proto-
       col 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 trans-
       ferring 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 trans-
       late the ends of lines to a standard representation which
       the receiver will then translate back into their local
       representation.  EBCDIC indicates the file being trans-
       ferred 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



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       between the two machines (in theory - in practice you
       should only use this if you really know what you're
       doing).

CONSTRUCTOR
       new ([ HOST ] [, OPTIONS ])
           This is the constructor for a new Net::FTP object.
           "HOST" is the name of the remote host to which an FTP
           connection is required.

           "HOST" is optional. If "HOST" is not given then it may
           instead be passed as the "Host" option described
           below.

           "OPTIONS" are passed in a hash like fashion, using key
           and value pairs.  Possible options are:

           Host - FTP host to connect to. It may be a single
           scalar, as defined for the "PeerAddr" option in
           IO::Socket::INET, or a reference to an array with
           hosts to try in turn. The "host" method will return
           the value which was used to connect to the host.

           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 connec-
           tion 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 Net::Config.

           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 Net::Cmd)

           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.,



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           "\*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.

           LocalAddr - Local address to use for all socket con-
           nections, this argument will be passed to
           IO::Socket::INET

           If the constructor fails undef will be returned and an
           error message will be in $@

METHODS
       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.

       login ([LOGIN [,PASSWORD [, ACCOUNT] ] ])
           Log into the remote FTP server with the given login
           information. If no arguments are given then the
           "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 anony-
           mous then anonymous@ will be used for password.

           If the connection is via a firewall then the "autho-
           rize" method will be called with no arguments.

       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 "authorize" uses
           "Net::Netrc" to do a lookup.

       site (ARGS)
           Send a SITE command to the remote server and wait for
           a response.

           Returns most significant digit of the response code.

       ascii
           Transfer file in ASCII. CRLF translation will be done
           if required

       binary
           Transfer file in binary mode. No transformation will
           be done.

           Hint: If both server and client machines use the same
           line ending for text files, then it will be faster to
           transfer all files in binary mode.



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       rename ( OLDNAME, NEWNAME )
           Rename a file on the remote FTP server from "OLDNAME"
           to "NEWNAME". This is done by sending the RNFR and
           RNTO commands.

       delete ( FILENAME )
           Send a request to the server to delete "FILENAME".

       cwd ( [ DIR ] )
           Attempt to change directory to the directory given in
           $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 direc-
           tory to the root directory.

       cdup ()
           Change directory to the parent of the current direc-
           tory.

       pwd ()
           Returns the full pathname of the current directory.

       restart ( WHERE )
           Set the byte offset at which to begin the next data
           transfer. Net::FTP simply records this value and uses
           it when during the next data transfer. For this reason
           this method will not return an error, but setting it
           may cause a subsequent data transfer to fail.

       rmdir ( DIR [, RECURSE ])
           Remove the directory with the name "DIR". If "RECURSE"
           is true then "rmdir" will attempt to delete everything
           inside the directory.

       mkdir ( DIR [, RECURSE ])
           Create a new directory with the name "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.

       alloc ( SIZE [, RECORD_SIZE] )
           The alloc command allows you to give the ftp server a
           hint about the size of the file about to be transfered
           using the ALLO ftp command. Some storage systems use
           this to make intelligent decisions about how to store
           the file.  The "SIZE" argument represents the size of
           the file in bytes. The "RECORD_SIZE" argument indi-
           cates a mazimum record or page size for files sent
           with a record or page structure.

           The size of the file will be determined, and sent to
           the server automatically for normal files so that this
           method need only be called if you are transfering data



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           from a socket, named pipe, or other stream not associ-
           ated with a normal file.

       ls ( [ DIR ] )
           Get a directory listing of "DIR", or the current
           directory.

           In an array context, returns a list of lines returned
           from the server. In a scalar context, returns a refer-
           ence to a list.

       dir ( [ DIR ] )
           Get a directory listing of "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 refer-
           ence to a list.

       get ( REMOTE_FILE [, LOCAL_FILE [, WHERE]] )
           Get "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 encoun-
           tered undef is returned.

       put ( LOCAL_FILE [, REMOTE_FILE ] )
           Put a file on the remote server. "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 file-
           name if "REMOTE_FILE" is not given.

           NOTE: If for some reason the transfer does not com-
           plete and an error is returned then the contents that
           had been transfered will not be remove automatically.

       put_unique ( LOCAL_FILE [, REMOTE_FILE ] )
           Same as put but uses the "STOU" command.

           Returns the name of the file on the server.




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       append ( LOCAL_FILE [, REMOTE_FILE ] )
           Same as put but appends to the file on the remote
           server.

           Returns "REMOTE_FILE", or the generated remote file-
           name if "REMOTE_FILE" is not given.

       unique_name ()
           Returns the name of the last file stored on the server
           using the "STOU" command.

       mdtm ( FILE )
           Returns the modification time of the given file

       size ( FILE )
           Returns the size in bytes for the given file as stored
           on the remote server.

           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.

       supported ( CMD )
           Returns TRUE if the remote server supports the given
           command.

       hash ( [FILEHANDLE_GLOB_REF],[ BYTES_PER_HASH_MARK] )
           Called without parameters, or with the first argument
           false, hash marks are suppressed.  If the first argu-
           ment is true but not a reference to a file handle
           glob, then \*STDERR is used.  The second argument is
           the number of bytes per hash mark printed, and
           defaults to 1024.  In all cases the return value is a
           reference to an array of two:  the filehandle glob
           reference and the bytes per hash mark.

       The following methods can return different results depend-
       ing 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 ( [ DIR ] )
           Send an "NLST" command to the server, with an optional
           parameter.

       list ( [ DIR ] )
           Same as "nlst" but using the "LIST" command





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       retr ( FILE )
           Begin the retrieval of a file called "FILE" from the
           remote server.

       stor ( FILE )
           Tell the server that you wish to store a file. "FILE"
           is the name of the new file that should be created.

       stou ( FILE )
           Same as "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.

       appe ( FILE )
           Tell the server that we want to append some data to
           the end of a file called "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 call-
       ing 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 ( [ PORT ] )
           Send a "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.

       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 "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.

       pasv_xfer ( SRC_FILE, DEST_SERVER [, DEST_FILE ] )
           This method will do a file transfer between two remote
           ftp servers. If "DEST_FILE" is omitted then the leaf
           name of "SRC_FILE" will be used.

       pasv_xfer_unique ( SRC_FILE, DEST_SERVER [, DEST_FILE ] )
           Like "pasv_xfer" but the file is stored on the remote
           server using the STOU command.




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       pasv_wait ( NON_PASV_SERVER )
           This method can be used to wait for a transfer to com-
           plete between a passive server and a non-passive
           server. The method should be called on the passive
           server with the "Net::FTP" object for the non-passive
           server passed as an argument.

       abort ()
           Abort the current data transfer.

       quit ()
           Send the QUIT command to the remote FTP server and
           close the socket connection.

       Methods for the adventurous

       "Net::FTP" inherits from "Net::Cmd" so methods defined in
       "Net::Cmd" may be used to send commands to the remote FTP
       server.

       quot (CMD [,ARGS])
           Send a command, that Net::FTP does not directly sup-
           port, to the remote server and wait for a response.

           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.

THE dataconn CLASS
       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.

       read ( BUFFER, SIZE [, TIMEOUT ] )
           Read "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.

       write ( BUFFER, SIZE [, TIMEOUT ] )
           Write "SIZE" bytes of data from "BUFFER" to the
           server, also performing any <CRLF> translation neces-
           sary. "TIMEOUT" is optional, if not given, the timeout
           value from the command connection will be used.




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           Returns the number of bytes written before any <CRLF>
           translation.

       bytes_read ()
           Returns the number of bytes read so far.

       abort ()
           Abort the current data transfer.

       close ()
           Close the data connection and get a response from the
           FTP server. Returns true if the connection was closed
           successfully and the first digit of the response from
           the server was a '2'.

UNIMPLEMENTED
       The following RFC959 commands have not been implemented:

       SMNT
           Mount a different file system structure without chang-
           ing login or accounting information.

       HELP
           Ask the server for "helpful information" (that's what
           the RFC says) on the commands it accepts.

       MODE
           Specifies transfer mode (stream, block or compressed)
           for file to be transferred.

       SYST
           Request remote server system identification.

       STAT
           Request remote server status.

       STRU
           Specifies file structure for file to be transferred.

       REIN
           Reinitialize the connection, flushing all I/O and
           account information.

REPORTING BUGS
       When reporting bugs/problems please include as much infor-
       mation as possible.  It may be difficult for me to repro-
       duce 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 con-
       structor, 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



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       problem.

AUTHOR
       Graham Barr <gbarrATpobox.com>

SEE ALSO
       Net::Netrc Net::Cmd

       ftp(1), ftpd(8), RFC 959
       http://www.cis.ohio-state.edu/htbin/rfc/rfc959.html

USE EXAMPLES
       For an example of the use of Net::FTP see

       http://www.csh.rit.edu/~adam/Progs/
           "autoftp" is a program that can retrieve, send, or
           list files via the FTP protocol in a non-interactive
           manner.

CREDITS
       Henry Gabryjelski <henrygATWPI.EDU> - for the suggestion of
       creating directories recursively.

       Nathan Torkington <gnatATfrii.com> - for some input on the
       documentation.

       Roderick Schertler <roderickATgate.net> - for various
       inputs

COPYRIGHT
       Copyright (c) 1995-2004 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.
























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