Tribblix: manual page: ftp.1

FTP(1) User Commands FTP(1)

NAME

ftp - file transfer program

SYNOPSIS

ftp [-adfginpstvx] [-m GSS Mech] [-T timeout]
[hostname [port]]

DESCRIPTION

The ftp command is the user interface to the Internet standard File
Transfer Protocol (FTP). ftp transfers files to and from a remote
network site.

The host and optional port with which ftp is to communicate can be
specified on the command line. If this is done, ftp immediately
attempts to establish a connection to an FTP server on that host.
Otherwise, ftp enters its command interpreter and awaits instructions
from the user. When ftp is awaiting commands from the user, it
displays the prompt ftp>.

OPTIONS

The following options can be specified at the command line, or to the
command interpreter:

-a
Uses GSSAPI authentication only. If the authentication
fails, this option closes the connection.

-d
Enables debugging.

-f
Forwards local security credentials to the remote
server.

-g
Disables filename "globbing".

-i
Turns off interactive prompting during multiple file
transfers.

-m
Specifies the GSS-API mechanism to use. The default is
to use the kerberos_v5 mechanism. Supported
alternatives are defined in /etc/gss/mech (see
mech(5)).

-n
Does not attempt "auto-login" upon initial connection.
If auto-login is not disabled, ftp checks the .netrc
file in the user's home directory for an entry
describing an account on the remote machine. If no
entry exists, ftp prompts for the login name of the
account on the remote machine (the default is the login
name on the local machine), and, if necessary, prompts
for a password and an account with which to login.

-p
Enables passive mode for data transfers. This command
is useful when connecting to a remote host from behind
a connection filtering firewall.

-s
Skips the SYST command that is sent by default to all
remote servers upon connection. The system command is
what enables the automatic use of binary mode rather
than the protocol default ascii mode.

As some older servers cannot handle the ftp command,
this directive is provided to allow inter-operability
with these servers.

-t
Enables packet tracing (unimplemented).

-T timeout
Enables global connection timer, specified in seconds
(decimal). There is a timer for the control connection
that is reset when anything is sent to the server and
disabled while the client is prompting for user input.
Another independent timer is used to monitor incoming
or outgoing data connections.

-v
Shows all responses from the remote server, as well as
report on data transfer statistics. This is turned on
by default if ftp is running interactively with its
input coming from the user's terminal.

-x
Attempts to use GSSAPI for authentication and
encryption. Data and Command channel protection is set
to "private".

The following commands can be specified to the command interpreter:

!

[ command ] Runs command as a shell command on the local machine.
If no command is given, invokes an interactive shell.

$ macro-name [ args ]

Executes the macro macro-name that was defined with the macdef
command. Arguments are passed to the macro unglobbed.

account [ passwd ]

Supplies a supplemental password required by a remote system for
access to resources once a login has been successfully completed.
If no argument is included, the user is prompted for an account
password in a non-echoing input mode.

append local-file [ remote-file ]

Appends a local file to a file on the remote machine. If remote-
file is not specified, the local file name is used, subject to
alteration by any ntrans or nmap settings. File transfer uses the
current settings for "representation type", "file structure", and
"transfer mode".

ascii

Sets the "representation type" to "network ASCII". This is the
default type.

bell

Sounds a bell after each file transfer command is completed.

binary

Sets the "representation type" to "image".

bye

Terminates the FTP session with the remote server and exit ftp.
An EOF also terminates the session and exit.

case

Toggles remote computer file name case mapping during mget
commands. When case is on (default is off), remote computer file
names with all letters in upper case are written in the local
directory with the letters mapped to lower case.

cd remote-directory

Changes the working directory on the remote machine to remote-
directory.

cdup

Changes the remote machine working directory to the parent of the
current remote machine working directory.

clear

Sets the protection level on data transfers to "clear". If no
ADAT command succeeded, then this is the default protection
level.

close

Terminates the FTP session with the remote server, and return to
the command interpreter. Any defined macros are erased.

cr

Toggles RETURN stripping during "network ASCII" type file
retrieval. Records are denoted by a RETURN/LINEFEED sequence
during "network ASCII" type file transfer. When cr is on (the
default), RETURN characters are stripped from this sequence to
conform with the UNIX system single LINEFEED record delimiter.
Records on non-UNIX-system remote hosts can contain single
LINEFEED characters; when an "network ASCII" type transfer is
made, these LINEFEED characters can be distinguished from a
record delimiter only when cr is off.

delete remote-file

Deletes the file remote-file on the remote machine.

debug

Toggles debugging mode. When debugging is on, ftp prints each
command sent to the remote machine, preceded by the string ->.

dir [ remote-directory [ local-file ]]

Prints a listing of the directory contents in the directory,
remote-directory, and, optionally, placing the output in local-
file. If no directory is specified, the current working directory
on the remote machine is used. If no local file is specified, or
local-file is -, output is sent to the terminal.

disconnect

A synonym for close.

form [ format-name ]

Sets the carriage control format subtype of the "representation
type" to format-name. The only valid format-name is non-print,
which corresponds to the default "non-print" subtype.

get remote-file [ local-file ]

Retrieves the remote-file and store it on the local machine. If
the local file name is not specified, it is given the same name
it has on the remote machine, subject to alteration by the
current case, ntrans, and nmap settings. The current settings for
"representation type", "file structure", and "transfer mode" are
used while transferring the file.

glob

Toggles filename expansion, or "globbing", for mdelete, mget and
mput. If globbing is turned off, filenames are taken literally.

Globbing for mput is done as in sh(1). For mdelete and mget, each
remote file name is expanded separately on the remote machine,
and the lists are not merged.

Expansion of a directory name is likely to be radically different
from expansion of the name of an ordinary file: the exact result
depends on the remote operating system and FTP server, and can be
previewed with the command, mls remote-files -.

mget and mput are not meant to transfer entire directory subtrees
of files. You can do this by transferring a tar(1) archive of the
subtree (using a "representation type" of "image" as set by the
binary command).

hash

Toggles hash-sign (#) printing for each data block transferred.
The size of a data block is 8192 bytes.

help [ command ]

Prints an informative message about the meaning of command. If no
argument is given, ftp prints a list of the known commands.

lcd [ directory ]

Changes the working directory on the local machine. If no
directory is specified, the user's home directory is used.

ls [ -al | remote-directory [ local-file ]]

By default, prints an abbreviated listing of the contents of a
directory on the remote machine. This default behavior can be
changed to make ls a synonym of the dir command. This change can
be achieved by setting FTP_LS_SENDS_NLST to 'no' in
/etc/default/ftp or in the environment. See ftp(5) for details.

The -a option lists all entries, including those that begin with
a dot (.), which are normally not listed. The -l option lists
files in long format, giving mode, number of links, owner, group,
size in bytes, and time of last modification for each file. If
the file is a special file, the size field instead contains the
major and minor device numbers rather than a size. If the file is
a symbolic link, the filename is printed followed by "->" and the
pathname of the referenced file.

If remote-directory is left unspecified, the current working
directory is used.

If no local file is specified, or if local-file is -, the output
is sent to the terminal.

macdef macro-name

Defines a macro. Subsequent lines are stored as the macro macro-
name. A null line (consecutive NEWLINE characters in a file or
RETURN characters from the terminal) terminates macro input mode.
There is a limit of 16 macros and 4096 total characters in all
defined macros. Macros remain defined until a close command is
executed.

The macro processor interprets $ and \ as special characters. A $
followed by a number (or numbers) is replaced by the
corresponding argument on the macro invocation command line. A $
followed by an i signals that macro processor that the executing
macro is to be looped. On the first pass, $i is replaced by the
first argument on the macro invocation command line; on the
second pass, it is replaced by the second argument, and so on. A
\ followed by any character is replaced by that character. Use
the \ to prevent special treatment of the $.

mdelete remote-files

Deletes the remote-files on the remote machine.

mdir remote-files local-file

Like dir, except multiple remote files can be specified. If
interactive prompting is on, ftp prompts the user to verify that
the last argument is indeed the target local file for receiving
mdir output.

mget remote-files

Expands the remote-files on the remote machine and do a get for
each file name thus produced. See glob for details on the
filename expansion. Resulting file names are processed according
to case, ntrans, and nmap settings. Files are transferred into
the local working directory, which can be changed with lcd
directory. New local directories can be created with ! mkdir
directory.

mkdir directory-name

Makes a directory on the remote machine.

mls remote-files local-file

Like ls(1), except multiple remote files can be specified. If
interactive prompting is on, ftp prompts the user to verify that
the last argument is indeed the target local file for receiving
mls output.

mode [ mode-name ]

Sets the "transfer mode" to mode-name. The only valid mode-name
is stream, which corresponds to the default "stream" mode. This
implementation only supports stream, and requires that it be
specified.

mput local-files

Expands wild cards in the list of local files given as arguments
and do a put for each file in the resulting list. See glob for
details of filename expansion. Resulting file names are processed
according to ntrans and nmap settings.

nlist [ -al | remote-directory [ local-file ]]

Prints an abbreviated listing of the contents of a directory on
the remote machine, listing only those files that can be
retrieved by the get command, unless the -a or -l option is used.
If remote-directory is left unspecified, the current working
directory is used.

The -a option lists all entries, including those that begin with
a dot (.), which are normally not listed. The -l option lists
files in long format the same way it does when used with the ls
command.

nmap [ inpattern outpattern ]

Sets or unsets the filename mapping mechanism. If no arguments
are specified, the filename mapping mechanism is unset. If
arguments are specified, remote filenames are mapped during mput
commands and put commands issued without a specified remote
target filename. If arguments are specified, local filenames are
mapped during mget commands and get commands issued without a
specified local target filename.

This command is useful when connecting to a non-UNIX-system
remote host with different file naming conventions or practices.
The mapping follows the pattern set by inpattern and outpattern.
inpattern is a template for incoming filenames (which can have
already been processed according to the ntrans and case
settings). Variable templating is accomplished by including the
sequences $1, $2, ..., $9 in inpattern. Use \ to prevent this
special treatment of the $ character. All other characters are
treated literally, and are used to determine the nmap inpattern
variable values.

For example, given inpattern $1.$2 and the remote file name
mydata.data, $1 would have the value mydata, and $2 would have
the value data.

The outpattern determines the resulting mapped filename. The
sequences $1, $2, ..., $9 are replaced by any value resulting
from the inpattern template. The sequence $0 is replaced by the
original filename. Additionally, the sequence [seq1,seq2] is
replaced by seq1 if seq1 is not a null string; otherwise it is
replaced by seq2.

For example, the command nmap $1.$2.$3 [$1,$2].[$2,file] would
yield the output filename myfile.data for input filenames
myfile.data and myfile.data.old, myfile.file for the input
filename myfile, and myfile.myfile for the input filename
.myfile. SPACE characters can be included in outpattern, as in
the example nmap $1 | sed "s/ *$//" > $1. Use the \ character to
prevent special treatment of the $, [, ], and ,, characters.

ntrans [ inchars [ outchars ] ]

Sets or unsets the filename character translation mechanism. If
no arguments are specified, the filename character translation
mechanism is unset. If arguments are specified, characters in
remote filenames are translated during mput commands and put
commands issued without a specified remote target filename, and
characters in local filenames are translated during mget commands
and get commands issued without a specified local target
filename.

This command is useful when connecting to a non-UNIX-system
remote host with different file naming conventions or practices.
Characters in a filename matching a character in inchars are
replaced with the corresponding character in outchars. If the
character's position in inchars is longer than the length of
outchars, the character is deleted from the file name.

Only 16 characters can be translated when using the ntrans
command under ftp. Use case (described above) if needing to
convert the entire alphabet.

open host [ port ]

Establishes a connection to the specified host FTP server. An
optional port number can be supplied, in which case, ftp attempts
to contact an FTP server at that port. If the auto-login option
is on (default setting), ftp also attempts to automatically log
the user in to the FTP server.

passive

Toggles passive mode. When passive mode is turned on, the ftp
client sends the PASV command requesting that the FTP server open
a port for the data connection and return the address of that
port. The remote server listens on that port and the client
connects to it. When passive mode is turned off, the ftp client
sends the PORT command to the server specifying an address for
the remote server to connect back to. Passive mode is useful when
the connections to the ftp client are controlled, for example,
when behind a firewall. When connecting to an IPv6-enabled FTP
server, EPSV can be used in place of PASV and EPRT in place of
PORT.

private

Sets the protection level on data transfers to "private". Data
transmissions are confidentiality-- and integrity--protected by
encryption. If no ADAT command succeeded, then the only possible
level is "clear".

prompt

Toggles interactive prompting. Interactive prompting occurs
during multiple file transfers to allow the user to selectively
retrieve or store files. By default, prompting is turned on. If
prompting is turned off, any mget or mput transfers all files,
and any mdelete deletes all files.

protect protection-level

Sets the protection level on data transfers to protection-level.
The valid protection levels are "clear" for unprotected data
transmissions, "safe" for data transmissions that are integrity-
protected by cryptographic checksum, and "private" for data
transmissions that are confidentiality-- and integrity--
protected by encryption. If no ADAT command succeeded, then the
only possible level is "clear". If no level is specified, the
current level is printed. The default protection level is
"clear".

proxy ftp-command

Executes an FTP command on a secondary control connection. This
command allows simultaneous connection to two remote FTP servers
for transferring files between the two servers. The first proxy
command should be an open, to establish the secondary control
connection. Enter the command proxy ? to see other FTP commands
executable on the secondary connection.

The following commands behave differently when prefaced by proxy:
open does not define new macros during the auto-login process,
close does not erase existing macro definitions, get and mget
transfer files from the host on the primary control connection to
the host on the secondary control connection, and put, mputd, and
append transfer files from the host on the secondary control
connection to the host on the primary control connection.

Third party file transfers depend upon support of the PASV
command by the server on the secondary control connection.

put local-file [ remote-file ]

Stores a local file on the remote machine. If remote-file is left
unspecified, the local file name is used after processing
according to any ntrans or nmap settings in naming the remote
file. File transfer uses the current settings for "representation
type", "file structure", and "transfer mode".

pwd

Prints the name of the current working directory on the remote
machine.

quit

A synonym for bye.

quote arg1 arg2 ...

Sends the arguments specified, verbatim, to the remote FTP
server. A single FTP reply code is expected in return. (The
remotehelp command displays a list of valid arguments.)

quote should be used only by experienced users who are familiar
with the FTP protocol.

recv remote-file [ local-file ]

A synonym for get.

reget remote-file [ local-file ]

The reget command acts like get, except that if local-file exists
and is smaller than remote-file, local-file is presumed to be a
partially transferred copy of remote-file and the transfer is
continued from the apparent point of failure. This command is
useful when transferring large files over networks that are prone
to dropping connections.

remotehelp [ command-name ]

Requests help from the remote FTP server. If a command-name is
specified it is supplied to the server as well.

rename from to

Renames the file from on the remote machine to have the name to.

reset

Clears reply queue. This command re-synchronizes command/reply
sequencing with the remote FTP server. Resynchronization can be
necessary following a violation of the FTP protocol by the remote
server.

restart [ marker ]

Restarts the immediately following get or put at the indicated
marker. On UNIX systems, marker is usually a byte offset into the
file. When followed by an mget, the restart applies to the first
get performed. Specifying a marker of 0 clears the restart
marker. If no argument is specified, the current restart status
is displayed.

rmdir directory-name

Deletes a directory on the remote machine.

runique

Toggles storing of files on the local system with unique
filenames. If a file already exists with a name equal to the
target local filename for a get or mget command, a .1 is appended
to the name. If the resulting name matches another existing file,
a .2 is appended to the original name. If this process continues
up to .99, an error message is printed, and the transfer does not
take place. The generated unique filename is reported. runique
does not affect local files generated from a shell command. The
default value is off.

safe

Sets the protection level on data transfers to "safe". Data
transmissions are integrity-protected by cryptographic checksum.
If no ADAT command succeeded, then the only possible level is
"clear".

send local-file [ remote-file ]

A synonym for put.

sendport

Toggles the use of PORT commands. By default, ftp attempts to use
a PORT command when establishing a connection for each data
transfer. The use of PORT commands can prevent delays when
performing multiple file transfers. If the PORT command fails,
ftp uses the default data port. When the use of PORT commands is
disabled, no attempt is made to use PORT commands for each data
transfer. This is useful when connected to certain FTP
implementations that ignore PORT commands but incorrectly
indicate they have been accepted.

site arg1 [ arg2 ] ...

Sends the arguments specified, verbatim, to the remote FTP server
as a SITE command.

status

Show the current status of ftp.

struct [ struct-name ]

Sets the file structure to struct-name. The only valid struct-
name is file, which corresponds to the default "file" structure.
The implementation only supports file, and requires that it be
specified.

sunique

Toggles storing of files on remote machine under unique file
names. The remote FTP server must support the STOU command for
successful completion. The remote server reports the unique
name. Default value is off.

tcpwindow [ size ]

Sets the TCP window size to be used for data connections.
Specifying a size of 0 stops the explicit setting of the TCP
window size on data connections. If no argument is specified, the
current setting is displayed.

tenex

Sets the "representation type" to that needed to talk to TENEX
machines.

trace

Toggles packet tracing (unimplemented).

type [ type-name ]

Sets the "representation type" to type-name. The valid type-names
are ascii for "network ASCII", binary or image for "image", and
tenex for "local byte size" with a byte size of 8 (used to talk
to TENEX machines). If no type is specified, the current type is
printed. The default type is "network ASCII".

user user-name [ password [ account ]]

Identify yourself to the remote FTP server. If the password is
not specified and the server requires it, ftp prompts the user
for it (after disabling local echo). If an account field is not
specified, and the FTP server requires it, the user is prompted
for it. If an account field is specified, an account command is
relayed to the remote server after the login sequence is
completed if the remote server did not require it for logging in.
Unless ftp is invoked with "auto-login" disabled, this process is
done automatically on initial connection to the FTP server.

verbose

Toggles verbose mode. In verbose mode, all responses from the FTP
server are displayed to the user. In addition, if verbose mode is
on, when a file transfer completes, statistics regarding the
efficiency of the transfer are reported. By default, verbose mode
is on if ftp's commands are coming from a terminal, and off
otherwise.

? [ command ]

A synonym for help.

Command arguments which have embedded spaces can be quoted with quote
(") marks.

If any command argument which is not indicated as being optional is
not specified, ftp prompts for that argument.

ABORTING A FILE TRANSFER

To abort a file transfer, use the terminal interrupt key. Sending
transfers is immediately halted. Receiving transfers are halted by
sending an FTP protocol ABOR command to the remote server, and
discarding any further data received. The speed at which this is
accomplished depends upon the remote server's support for ABOR
processing. If the remote server does not support the ABOR command,
an ftp> prompt does not appear until the remote server has completed
sending the requested file.

The terminal interrupt key sequence is ignored when ftp has completed
any local processing and is awaiting a reply from the remote server.
A long delay in this mode can result from the ABOR processing
described above, or from unexpected behavior by the remote server,
including violations of the ftp protocol. If the delay results from
unexpected remote server behavior, the local ftp program must be
killed by hand.

FILE NAMING CONVENTIONS

Local files specified as arguments to ftp commands are processed
according to the following rules.

1)
If the file name - is specified, the standard input (for
reading) or standard output (for writing) is used.

2)
If the first character of the file name is |, the remainder of
the argument is interpreted as a shell command. ftp then forks
a shell, using popen(3C) with the argument supplied, and reads
(writes) from the standard output (standard input) of that
shell. If the shell command includes SPACE characters, the
argument must be quoted; for example "| ls -lt". A particularly
useful example of this mechanism is: "dir | more".

3)
Failing the above checks, if globbing is enabled, local file
names are expanded according to the rules used in the sh(1);
see the glob command. If the ftp command expects a single local
file (for example, put), only the first filename generated by
the globbing operation is used.

4)
For mget commands and get commands with unspecified local file
names, the local filename is the remote filename, which can be
altered by a case, ntrans, or nmap setting. The resulting
filename can then be altered if runique is on.

5)
For mput commands and put commands with unspecified remote file
names, the remote filename is the local filename, which can be
altered by a ntrans or nmap setting. The resulting filename can
then be altered by the remote server if sunique is on.

FILE TRANSFER PARAMETERS

The FTP specification specifies many parameters which can affect a
file transfer.

The "representation type" can be one of "network ASCII", "EBCDIC",
"image", or "local byte size" with a specified byte size (for
PDP-10's and PDP-20's mostly). The "network ASCII" and "EBCDIC" types
have a further subtype which specifies whether vertical format
control (NEWLINE characters, form feeds, and so on) are to be passed
through ("non-print"), provided in TELNET format ("TELNET format
controls"), or provided in ASA (FORTRAN) ("carriage control (ASA)")
format. ftp supports the "network ASCII" (subtype "non-print" only)
and "image" types, plus "local byte size" with a byte size of 8 for
communicating with TENEX machines.

The "file structure" can be one of file (no record structure),
record, or page. ftp supports only the default value, which is file.

The "transfer mode" can be one of stream, block, or compressed. ftp
supports only the default value, which is stream.

USAGE

See largefile(7) for the description of the behavior of ftp when
encountering files greater than or equal to 2 Gbyte (2^31 bytes).

The ftp command is IPv6-enabled. See ip6(4P).

FILES

~/.netrc

ATTRIBUTES

See attributes(7) for descriptions of the following attributes:

+---------------+-----------------+
|ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+---------------+-----------------+
|CSI | enabled |
+---------------+-----------------+

NOTES

Failure to log in can arise from an explicit denial by the remote FTP
server because the account is listed in /etc/ftpusers. See
ftpusers(5).

Correct execution of many commands depends upon proper behavior by
the remote server.

An error in the treatment of carriage returns in the 4.2 BSD code
handling transfers with a "representation type" of "network ASCII"
has been corrected. This correction can result in incorrect transfers
of binary files to and from 4.2 BSD servers using a "representation
type" of "network ASCII". Avoid this problem by using the "image"
type.

June 6, 2006 FTP(1)