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
~/.netrcATTRIBUTES
See
attributes(7) for descriptions of the following attributes:
+---------------+-----------------+
|ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+---------------+-----------------+
|CSI | enabled |
+---------------+-----------------+
SEE ALSO
ls(1),
rcp(1),
sh(1),
tar(1),
popen(3C),
ip6(4P),
ftp(5),
ftpusers(5),
mech(5),
netrc(5),
attributes(7),
largefile(7) Allman, M., Ostermann, S., and Metz, C.
RFC 2428, FTP Extensions for IPv6 and NATs. The Internet Society. September 1998.
Lunt, S. J.
RFC 2228, FTP Security Extensions. Internet Draft. November
1993.
Postel, Jon, and Joyce Reynolds.
RFC 959, File Transfer Protocol (FTP ).
Network Information Center. October 1985.
Piscitello, D.
RFC 1639, FTP Operation Over Big Address Records (FOOBAR).
Network Working Group. June 1994.
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)