1Net::FTP(3pm)          Perl Programmers Reference Guide          Net::FTP(3pm)
2
3
4

NAME

6       Net::FTP - FTP Client class
7

SYNOPSIS

9           use Net::FTP;
10
11           $ftp = Net::FTP->new("some.host.name", Debug => 0)
12             or die "Cannot connect to some.host.name: $@";
13
14           $ftp->login("anonymous",'-anonymous@')
15             or die "Cannot login ", $ftp->message;
16
17           $ftp->cwd("/pub")
18             or die "Cannot change working directory ", $ftp->message;
19
20           $ftp->get("that.file")
21             or die "get failed ", $ftp->message;
22
23           $ftp->quit;
24

DESCRIPTION

26       "Net::FTP" is a class implementing a simple FTP client in Perl as
27       described in RFC959.  It provides wrappers for a subset of the RFC959
28       commands.
29

OVERVIEW

31       FTP stands for File Transfer Protocol.  It is a way of transferring
32       files between networked machines.  The protocol defines a client (whose
33       commands are provided by this module) and a server (not implemented in
34       this module).  Communication is always initiated by the client, and the
35       server responds with a message and a status code (and sometimes with
36       data).
37
38       The FTP protocol allows files to be sent to or fetched from the server.
39       Each transfer involves a local file (on the client) and a remote file
40       (on the server).  In this module, the same file name will be used for
41       both local and remote if only one is specified.  This means that
42       transferring remote file "/path/to/file" will try to put that file in
43       "/path/to/file" locally, unless you specify a local file name.
44
45       The protocol also defines several standard translations which the file
46       can undergo during transfer.  These are ASCII, EBCDIC, binary, and
47       byte.  ASCII is the default type, and indicates that the sender of
48       files will translate the ends of lines to a standard representation
49       which the receiver will then translate back into their local
50       representation.  EBCDIC indicates the file being transferred is in
51       EBCDIC format.  Binary (also known as image) format sends the data as a
52       contiguous bit stream.  Byte format transfers the data as bytes, the
53       values of which remain the same regardless of differences in byte size
54       between the two machines (in theory - in practice you should only use
55       this if you really know what you're doing).
56

CONSTRUCTOR

58       new ([ HOST ] [, OPTIONS ])
59           This is the constructor for a new Net::FTP object. "HOST" is the
60           name of the remote host to which an FTP connection is required.
61
62           "HOST" is optional. If "HOST" is not given then it may instead be
63           passed as the "Host" option described below.
64
65           "OPTIONS" are passed in a hash like fashion, using key and value
66           pairs.  Possible options are:
67
68           Host - FTP host to connect to. It may be a single scalar, as
69           defined for the "PeerAddr" option in IO::Socket::INET, or a
70           reference to an array with hosts to try in turn. The "host" method
71           will return the value which was used to connect to the host.
72
73           Firewall - The name of a machine which acts as an FTP firewall.
74           This can be overridden by an environment variable "FTP_FIREWALL".
75           If specified, and the given host cannot be directly connected to,
76           then the connection is made to the firewall machine and the string
77           @hostname is appended to the login identifier. This kind of setup
78           is also referred to as an ftp proxy.
79
80           FirewallType - The type of firewall running on the machine
81           indicated by Firewall. This can be overridden by an environment
82           variable "FTP_FIREWALL_TYPE". For a list of permissible types, see
83           the description of ftp_firewall_type in Net::Config.
84
85           BlockSize - This is the block size that Net::FTP will use when
86           doing transfers. (defaults to 10240)
87
88           Port - The port number to connect to on the remote machine for the
89           FTP connection
90
91           Timeout - Set a timeout value (defaults to 120)
92
93           Debug - debug level (see the debug method in Net::Cmd)
94
95           Passive - If set to a non-zero value then all data transfers will
96           be done using passive mode. If set to zero then data transfers will
97           be done using active mode.  If the machine is connected to the
98           Internet directly, both passive and active mode should work equally
99           well.  Behind most firewall and NAT configurations passive mode has
100           a better chance of working.  However, in some rare firewall
101           configurations, active mode actually works when passive mode
102           doesn't.  Some really old FTP servers might not implement passive
103           transfers.  If not specified, then the transfer mode is set by the
104           environment variable "FTP_PASSIVE" or if that one is not set by the
105           settings done by the libnetcfg utility.  If none of these apply
106           then passive mode is used.
107
108           Hash - If given a reference to a file handle (e.g., "\*STDERR"),
109           print hash marks (#) on that filehandle every 1024 bytes.  This
110           simply invokes the "hash()" method for you, so that hash marks are
111           displayed for all transfers.  You can, of course, call "hash()"
112           explicitly whenever you'd like.
113
114           LocalAddr - Local address to use for all socket connections, this
115           argument will be passed to IO::Socket::INET
116
117           If the constructor fails undef will be returned and an error
118           message will be in $@
119

METHODS

121       Unless otherwise stated all methods return either a true or false
122       value, with true meaning that the operation was a success. When a
123       method states that it returns a value, failure will be returned as
124       undef or an empty list.
125
126       login ([LOGIN [,PASSWORD [, ACCOUNT] ] ])
127           Log into the remote FTP server with the given login information. If
128           no arguments are given then the "Net::FTP" uses the "Net::Netrc"
129           package to lookup the login information for the connected host.  If
130           no information is found then a login of anonymous is used.  If no
131           password is given and the login is anonymous then anonymous@ will
132           be used for password.
133
134           If the connection is via a firewall then the "authorize" method
135           will be called with no arguments.
136
137       authorize ( [AUTH [, RESP]])
138           This is a protocol used by some firewall ftp proxies. It is used to
139           authorise the user to send data out.  If both arguments are not
140           specified then "authorize" uses "Net::Netrc" to do a lookup.
141
142       site (ARGS)
143           Send a SITE command to the remote server and wait for a response.
144
145           Returns most significant digit of the response code.
146
147       ascii
148           Transfer file in ASCII. CRLF translation will be done if required
149
150       binary
151           Transfer file in binary mode. No transformation will be done.
152
153           Hint: If both server and client machines use the same line ending
154           for text files, then it will be faster to transfer all files in
155           binary mode.
156
157       rename ( OLDNAME, NEWNAME )
158           Rename a file on the remote FTP server from "OLDNAME" to "NEWNAME".
159           This is done by sending the RNFR and RNTO commands.
160
161       delete ( FILENAME )
162           Send a request to the server to delete "FILENAME".
163
164       cwd ( [ DIR ] )
165           Attempt to change directory to the directory given in $dir.  If
166           $dir is "..", the FTP "CDUP" command is used to attempt to move up
167           one directory. If no directory is given then an attempt is made to
168           change the directory to the root directory.
169
170       cdup ()
171           Change directory to the parent of the current directory.
172
173       pwd ()
174           Returns the full pathname of the current directory.
175
176       restart ( WHERE )
177           Set the byte offset at which to begin the next data transfer.
178           Net::FTP simply records this value and uses it when during the next
179           data transfer. For this reason this method will not return an
180           error, but setting it may cause a subsequent data transfer to fail.
181
182       rmdir ( DIR [, RECURSE ])
183           Remove the directory with the name "DIR". If "RECURSE" is true then
184           "rmdir" will attempt to delete everything inside the directory.
185
186       mkdir ( DIR [, RECURSE ])
187           Create a new directory with the name "DIR". If "RECURSE" is true
188           then "mkdir" will attempt to create all the directories in the
189           given path.
190
191           Returns the full pathname to the new directory.
192
193       alloc ( SIZE [, RECORD_SIZE] )
194           The alloc command allows you to give the ftp server a hint about
195           the size of the file about to be transferred using the ALLO ftp
196           command. Some storage systems use this to make intelligent
197           decisions about how to store the file.  The "SIZE" argument
198           represents the size of the file in bytes. The "RECORD_SIZE"
199           argument indicates a maximum record or page size for files sent
200           with a record or page structure.
201
202           The size of the file will be determined, and sent to the server
203           automatically for normal files so that this method need only be
204           called if you are transferring data from a socket, named pipe, or
205           other stream not associated with a normal file.
206
207       ls ( [ DIR ] )
208           Get a directory listing of "DIR", or the current directory.
209
210           In an array context, returns a list of lines returned from the
211           server. In a scalar context, returns a reference to a list.
212
213       dir ( [ DIR ] )
214           Get a directory listing of "DIR", or the current directory in long
215           format.
216
217           In an array context, returns a list of lines returned from the
218           server. In a scalar context, returns a reference to a list.
219
220       get ( REMOTE_FILE [, LOCAL_FILE [, WHERE]] )
221           Get "REMOTE_FILE" from the server and store locally. "LOCAL_FILE"
222           may be a filename or a filehandle. If not specified, the file will
223           be stored in the current directory with the same leafname as the
224           remote file.
225
226           If "WHERE" is given then the first "WHERE" bytes of the file will
227           not be transferred, and the remaining bytes will be appended to the
228           local file if it already exists.
229
230           Returns "LOCAL_FILE", or the generated local file name if
231           "LOCAL_FILE" is not given. If an error was encountered undef is
232           returned.
233
234       put ( LOCAL_FILE [, REMOTE_FILE ] )
235           Put a file on the remote server. "LOCAL_FILE" may be a name or a
236           filehandle.  If "LOCAL_FILE" is a filehandle then "REMOTE_FILE"
237           must be specified. If "REMOTE_FILE" is not specified then the file
238           will be stored in the current directory with the same leafname as
239           "LOCAL_FILE".
240
241           Returns "REMOTE_FILE", or the generated remote filename if
242           "REMOTE_FILE" is not given.
243
244           NOTE: If for some reason the transfer does not complete and an
245           error is returned then the contents that had been transferred will
246           not be remove automatically.
247
248       put_unique ( LOCAL_FILE [, REMOTE_FILE ] )
249           Same as put but uses the "STOU" command.
250
251           Returns the name of the file on the server.
252
253       append ( LOCAL_FILE [, REMOTE_FILE ] )
254           Same as put but appends to the file on the remote server.
255
256           Returns "REMOTE_FILE", or the generated remote filename if
257           "REMOTE_FILE" is not given.
258
259       unique_name ()
260           Returns the name of the last file stored on the server using the
261           "STOU" command.
262
263       mdtm ( FILE )
264           Returns the modification time of the given file
265
266       size ( FILE )
267           Returns the size in bytes for the given file as stored on the
268           remote server.
269
270           NOTE: The size reported is the size of the stored file on the
271           remote server.  If the file is subsequently transferred from the
272           server in ASCII mode and the remote server and local machine have
273           different ideas about "End Of Line" then the size of file on the
274           local machine after transfer may be different.
275
276       supported ( CMD )
277           Returns TRUE if the remote server supports the given command.
278
279       hash ( [FILEHANDLE_GLOB_REF],[ BYTES_PER_HASH_MARK] )
280           Called without parameters, or with the first argument false, hash
281           marks are suppressed.  If the first argument is true but not a
282           reference to a file handle glob, then \*STDERR is used.  The second
283           argument is the number of bytes per hash mark printed, and defaults
284           to 1024.  In all cases the return value is a reference to an array
285           of two:  the filehandle glob reference and the bytes per hash mark.
286
287       feature ( NAME )
288           Determine if the server supports the specified feature. The return
289           value is a list of lines the server responded with to describe the
290           options that it supports for the given feature. If the feature is
291           unsupported then the empty list is returned.
292
293             if ($ftp->feature( 'MDTM' )) {
294               # Do something
295             }
296
297             if (grep { /\bTLS\b/ } $ftp->feature('AUTH')) {
298               # Server supports TLS
299             }
300
301       The following methods can return different results depending on how
302       they are called. If the user explicitly calls either of the "pasv" or
303       "port" methods then these methods will return a true or false value. If
304       the user does not call either of these methods then the result will be
305       a reference to a "Net::FTP::dataconn" based object.
306
307       nlst ( [ DIR ] )
308           Send an "NLST" command to the server, with an optional parameter.
309
310       list ( [ DIR ] )
311           Same as "nlst" but using the "LIST" command
312
313       retr ( FILE )
314           Begin the retrieval of a file called "FILE" from the remote server.
315
316       stor ( FILE )
317           Tell the server that you wish to store a file. "FILE" is the name
318           of the new file that should be created.
319
320       stou ( FILE )
321           Same as "stor" but using the "STOU" command. The name of the unique
322           file which was created on the server will be available via the
323           "unique_name" method after the data connection has been closed.
324
325       appe ( FILE )
326           Tell the server that we want to append some data to the end of a
327           file called "FILE". If this file does not exist then create it.
328
329       If for some reason you want to have complete control over the data
330       connection, this includes generating it and calling the "response"
331       method when required, then the user can use these methods to do so.
332
333       However calling these methods only affects the use of the methods above
334       that can return a data connection. They have no effect on methods
335       "get", "put", "put_unique" and those that do not require data
336       connections.
337
338       port ( [ PORT ] )
339           Send a "PORT" command to the server. If "PORT" is specified then it
340           is sent to the server. If not, then a listen socket is created and
341           the correct information sent to the server.
342
343       pasv ()
344           Tell the server to go into passive mode. Returns the text that
345           represents the port on which the server is listening, this text is
346           in a suitable form to sent to another ftp server using the "port"
347           method.
348
349       The following methods can be used to transfer files between two remote
350       servers, providing that these two servers can connect directly to each
351       other.
352
353       pasv_xfer ( SRC_FILE, DEST_SERVER [, DEST_FILE ] )
354           This method will do a file transfer between two remote ftp servers.
355           If "DEST_FILE" is omitted then the leaf name of "SRC_FILE" will be
356           used.
357
358       pasv_xfer_unique ( SRC_FILE, DEST_SERVER [, DEST_FILE ] )
359           Like "pasv_xfer" but the file is stored on the remote server using
360           the STOU command.
361
362       pasv_wait ( NON_PASV_SERVER )
363           This method can be used to wait for a transfer to complete between
364           a passive server and a non-passive server. The method should be
365           called on the passive server with the "Net::FTP" object for the
366           non-passive server passed as an argument.
367
368       abort ()
369           Abort the current data transfer.
370
371       quit ()
372           Send the QUIT command to the remote FTP server and close the socket
373           connection.
374
375   Methods for the adventurous
376       "Net::FTP" inherits from "Net::Cmd" so methods defined in "Net::Cmd"
377       may be used to send commands to the remote FTP server.
378
379       quot (CMD [,ARGS])
380           Send a command, that Net::FTP does not directly support, to the
381           remote server and wait for a response.
382
383           Returns most significant digit of the response code.
384
385           WARNING This call should only be used on commands that do not
386           require data connections. Misuse of this method can hang the
387           connection.
388

THE dataconn CLASS

390       Some of the methods defined in "Net::FTP" return an object which will
391       be derived from this class.The dataconn class itself is derived from
392       the "IO::Socket::INET" class, so any normal IO operations can be
393       performed.  However the following methods are defined in the dataconn
394       class and IO should be performed using these.
395
396       read ( BUFFER, SIZE [, TIMEOUT ] )
397           Read "SIZE" bytes of data from the server and place it into
398           "BUFFER", also performing any <CRLF> translation necessary.
399           "TIMEOUT" is optional, if not given, the timeout value from the
400           command connection will be used.
401
402           Returns the number of bytes read before any <CRLF> translation.
403
404       write ( BUFFER, SIZE [, TIMEOUT ] )
405           Write "SIZE" bytes of data from "BUFFER" to the server, also
406           performing any <CRLF> translation necessary. "TIMEOUT" is optional,
407           if not given, the timeout value from the command connection will be
408           used.
409
410           Returns the number of bytes written before any <CRLF> translation.
411
412       bytes_read ()
413           Returns the number of bytes read so far.
414
415       abort ()
416           Abort the current data transfer.
417
418       close ()
419           Close the data connection and get a response from the FTP server.
420           Returns true if the connection was closed successfully and the
421           first digit of the response from the server was a '2'.
422

UNIMPLEMENTED

424       The following RFC959 commands have not been implemented:
425
426       SMNT
427           Mount a different file system structure without changing login or
428           accounting information.
429
430       HELP
431           Ask the server for "helpful information" (that's what the RFC says)
432           on the commands it accepts.
433
434       MODE
435           Specifies transfer mode (stream, block or compressed) for file to
436           be transferred.
437
438       SYST
439           Request remote server system identification.
440
441       STAT
442           Request remote server status.
443
444       STRU
445           Specifies file structure for file to be transferred.
446
447       REIN
448           Reinitialize the connection, flushing all I/O and account
449           information.
450

REPORTING BUGS

452       When reporting bugs/problems please include as much information as
453       possible.  It may be difficult for me to reproduce the problem as
454       almost every setup is different.
455
456       A small script which yields the problem will probably be of help. It
457       would also be useful if this script was run with the extra options
458       "Debug =" 1> passed to the constructor, and the output sent with the
459       bug report. If you cannot include a small script then please include a
460       Debug trace from a run of your program which does yield the problem.
461

AUTHOR

463       Graham Barr <gbarr@pobox.com>
464

SEE ALSO

466       Net::Netrc Net::Cmd
467
468       ftp(1), ftpd(8), RFC 959
469       http://www.cis.ohio-state.edu/htbin/rfc/rfc959.html
470

USE EXAMPLES

472       For an example of the use of Net::FTP see
473
474       http://www.csh.rit.edu/~adam/Progs/
475           "autoftp" is a program that can retrieve, send, or list files via
476           the FTP protocol in a non-interactive manner.
477

CREDITS

479       Henry Gabryjelski <henryg@WPI.EDU> - for the suggestion of creating
480       directories recursively.
481
482       Nathan Torkington <gnat@frii.com> - for some input on the
483       documentation.
484
485       Roderick Schertler <roderick@gate.net> - for various inputs
486
488       Copyright (c) 1995-2004 Graham Barr. All rights reserved.  This program
489       is free software; you can redistribute it and/or modify it under the
490       same terms as Perl itself.
491
492
493
494perl v5.12.4                      2011-06-01                     Net::FTP(3pm)
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