NAME¶
ftp
—
ARPANET file transfer program
SYNOPSIS¶
ftp |
[ -K ]
[-d ]
[-g ]
[-i ]
[-l ]
[-n ]
[-p ]
[-t ]
[-v ]
[-x ]
[- -no-gss-bindings ]
[- -no-gss-delegate ]
[host ] |
DESCRIPTION¶
ftp
is the user interface to the ARPANET
standard File Transfer Protocol. The program allows a user to transfer files
to and from a remote network site.
Modifications have been made so that it almost follows the FTP Security
Extensions, RFC 2228.
Options may be specified at the command line, or to the command interpreter.
-K
- Disable Kerberos authentication.
-t
- Enables packet tracing.
-v
- Verbose option forces
ftp
to show all
responses from the remote server, as well as report on data transfer
statistics.
-n
- Restrains
ftp
from attempting
“auto-login” upon initial connection. If auto-login is
enabled, ftp
will check the
.netrc (see below) file in the user's
home directory for an entry describing an account on the remote machine.
If no entry exists, ftp
will prompt for
the remote machine login name (default is the user identity on the local
machine), and, if necessary, prompt for a password and an account with
which to login.
-i
- Turns off interactive prompting during multiple file transfers.
-p
- Turn on passive mode.
-d
- Enables debugging.
-g
- Disables file name globbing.
.It Fl Fl no-gss-bindings Don't use GSS-API bindings when talking to peer.
IP addresses will not be checked to ensure they match.
-
-no-gss-delegate
- Disable delegation of GSSAPI credentials.
-l
- Disables command line editing.
-x
- Encrypt command and data channel.
The client host with which
ftp
is to
communicate may be specified on the command line. If this is done,
ftp
will immediately attempt to establish a
connection to an FTP server on that host; otherwise,
ftp
will enter its command interpreter and
await instructions from the user. When
ftp
is awaiting commands from the user the prompt
‘
ftp>
’ is provided to the user. The
following commands are recognized by
ftp
:
!
[]
- Invoke an interactive shell on the local machine. If there are arguments,
the first is taken to be a command to execute directly, with the rest of
the arguments as its arguments.
$
macro-name
[args
]
- Execute the macro macro-name that was
defined with the
macdef
command.
Arguments are passed to the macro unglobbed.
account
[passwd
]
- Supply 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 will be prompted for an account password in a
non-echoing input mode.
append
local-file
[remote-file
]
- Append a local file to a file on the remote machine. If
remote-file is left unspecified, the
local file name is used in naming the remote file after being altered by
any
ntrans
or
nmap
setting. File transfer uses the
current settings for type
,
format
,
mode
, and
structure
.
ascii
- Set the file transfer
type
to network
ASCII. This is the default type.
bell
- Arrange that a bell be sounded after each file transfer command is
completed.
binary
- Set the file transfer
type
to support
binary image transfer.
bye
- Terminate the FTP session with the remote server and exit
ftp
. An end of file will also terminate
the session and exit.
case
- Toggle 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
- Change the working directory on the remote machine to
remote-directory.
cdup
- Change the remote machine working directory to the parent of the current
remote machine working directory.
chmod
mode file-name
- Change the permission modes of the file
file-name on the remote sytem to
mode.
close
- Terminate the FTP session with the remote server, and return to the
command interpreter. Any defined macros are erased.
cr
- Toggle carriage return stripping during ascii type file retrieval. Records
are denoted by a carriage return/linefeed sequence during ascii type file
transfer. When
cr
is on (the default),
carriage returns are stripped from this sequence to conform with the
UNIX single linefeed record delimiter. Records on
non-UNIX remote systems may contain single
linefeeds; when an ascii type transfer is made, these linefeeds may be
distinguished from a record delimiter only when
cr
is off.
delete
remote-file
- Delete the file remote-file on the remote
machine.
debug
[debug-value
]
- Toggle debugging mode. If an optional
debug-value is specified it is used to
set the debugging level. When debugging is on,
ftp
prints each command sent to the
remote machine, preceded by the string
‘-->
’
dir
[remote-directory
]
[local-file
]
- Print a listing of the directory contents in the directory,
remote-directory, and, optionally,
placing the output in local-file. If
interactive prompting is on,
ftp
will
prompt the user to verify that the last argument is indeed the target
local file for receiving dir
output. 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 comes to the terminal.
disconnect
- A synonym for close.
form
format
- Set the file transfer
form
to
format. The default format is
“file”.
get
remote-file
[local-file
]
- Retrieve 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
type
,
form
,
mode
, and
structure
are used while transferring
the file.
glob
- Toggle filename expansion for
mdelete
,
mget
and
mput
. If globbing is turned off with
glob
, the file name arguments are taken
literally and not expanded. Globbing for
mput
is done as in
csh(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 different from expansion of the name
of an ordinary file: the exact result depends on the foreign operating
system and ftp server, and can be previewed by doing
‘mls remote-files -
’. As a security
measure, remotely globbed files that starts with ‘/’ or
contains ‘../’, will not be automatically received. If you
have interactive prompting turned off, these filenames will be ignored.
Note: mget
and
mput
are not meant to transfer entire
directory subtrees of files. That can be done by transferring a
tar(1) archive of the subtree (in binary
mode).
hash
- Toggle hash-sign (``#'') printing for each data block transferred. The
size of a data block is 1024 bytes.
help
[command
]
- Print an informative message about the meaning of
command. If no argument is given,
ftp
prints a list of the known
commands.
idle
[seconds
]
- Set the inactivity timer on the remote server to
seconds seconds. If
seconds is omitted, the current
inactivity timer is printed.
lcd
[directory
]
- Change the working directory on the local machine. If no
directory is specified, the user's home
directory is used.
ls
[remote-directory
]
[local-file
]
- Print a listing of the contents of a directory on the remote machine. The
listing includes any system-dependent information that the server chooses
to include; for example, most UNIX systems will
produce output from the command ‘
ls
-l
’. (See also nlist
.) If
remote-directory is left unspecified, the
current working directory is used. If interactive prompting is on,
ftp
will prompt the user to verify that
the last argument is indeed the target local file for receiving
ls
output. If no local file is
specified, or if local-file is
‘-
’, the output is sent
to the terminal.
macdef
macro-name
- Define a macro. Subsequent lines are stored as the macro
macro-name; a null line (consecutive
newline characters in a file or carriage returns 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
]
- Delete the remote-files on the remote
machine.
mdir
remote-files local-file
- Like
dir
, except multiple remote files
may be specified. If interactive prompting is on,
ftp
will prompt the user to verify that
the last argument is indeed the target local file for receiving
mdir
output.
mget
remote-files
- Expand 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 will then be 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
- Make a directory on the remote machine.
mls
remote-files local-file
- Like
nlist
, except multiple remote
files may be specified, and the
local-file must be specified. If
interactive prompting is on, ftp
will
prompt the user to verify that the last argument is indeed the target
local file for receiving mls
output.
mode
[mode-name
]
- Set the file transfer
mode
to
mode-name. The default mode is
“stream” mode.
modtime
file-name
- Show the last modification time of the file on the remote machine.
mput
local-files
- Expand 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 will then be processed according to
ntrans
and
nmap
settings.
newer
file-name
- Get the file only if the modification time of the remote file is more
recent that the file on the current system. If the file does not exist on
the current system, the remote file is considered
newer
. Otherwise, this command is
identical to get.
nlist
[remote-directory
]
[local-file
]
- Print a list of the files in a directory on the remote machine. If
remote-directory is left unspecified, the
current working directory is used. If interactive prompting is on,
ftp
will prompt the user to verify that
the last argument is indeed the target local file for receiving
nlist
output. If no local file is
specified, or if local-file is
-
, the output is sent to the
terminal.
nmap
[inpattern
outpattern
]
- Set or unset 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 remote computer
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 may 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 replace 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".
Spaces may 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
[]
- Set or unset 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. If arguments are specified, 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
remote computer 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.
open
host
[port
]
- Establish a connection to the specified
host FTP server. An optional port number
may be supplied, in which case,
ftp
will attempt to contact an FTP server at that port. If the
auto-login
option is on (default),
ftp
will also attempt to automatically
log the user in to the FTP server (see below).
passive
- Toggle passive mode. If passive mode is turned on (default is off), the
ftp client will send a
PASV
command for
all data connections instead of the usual
PORT
command. The
PASV
command requests that the remote
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 using the more traditional
PORT
command, the client listens on a
port and sends that address to the remote server, who connects back to it.
Passive mode is useful when using ftp
through a gateway router or host that controls the directionality of
traffic. (Note that though ftp servers are required to support the
PASV
command by RFC 1123, some do
not.)
prompt
- Toggle interactive prompting. Interactive prompting occurs during multiple
file transfers to allow the user to selectively retrieve or store files.
If prompting is turned off (default is on), any
mget
or
mput
will transfer all files, and any
mdelete
will delete all files.
proxy
ftp-command
- Execute 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
will not define new macros during
the auto-login process, close
will 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
,
mput
, 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 ftp
protocol PASV
command by the server on
the secondary control connection.
put
local-file
[remote-file
]
- Store 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
type
,
format
,
mode
, and
structure
.
pwd
- Print the name of the current working directory on the remote
machine.
quit
- A synonym for
bye
.
quote
arg1 arg2 ...
- The arguments specified are sent, verbatim, to the remote FTP server.
recv
remote-file
[local-file
]
- A synonym for get.
reget
remote-file
[local-file
]
- Reget 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 very large files over networks that are prone to
dropping connections.
remotehelp
[command-name
]
- Request help from the remote FTP server. If a
command-name is specified it is supplied
to the server as well.
remotestatus
[file-name
]
- With no arguments, show status of remote machine. If
file-name is specified, show status of
file-name on remote machine.
rename
[from
]
[to
]
- Rename the file from on the remote
machine, to the file to.
reset
- Clear reply queue. This command re-synchronizes command/reply sequencing
with the remote ftp server. Resynchronization may be necessary following a
violation of the ftp protocol by the remote server.
restart
marker
- Restart the immediately following
get
or put
at the indicated
marker. On UNIX
systems, marker is usually a byte offset into the file.
rmdir
directory-name
- Delete a directory on the remote machine.
runique
- Toggle 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 will be
reported. Note that runique
will not
affect local files generated from a shell command (see below). The default
value is off.
send
local-file
[remote-file
]
- A synonym for put.
sendport
- Toggle the use of
PORT
commands. By
default, ftp
will attempt 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
will use the default data port.
When the use of PORT
commands is
disabled, no attempt will be made to use
PORT
commands for each data transfer.
This is useful for certain FTP implementations which do ignore
PORT
commands but, incorrectly,
indicate they've been accepted.
site
arg1 arg2 ...
- The arguments specified are sent, verbatim, to the remote FTP server as a
SITE
command.
size
file-name
- Return size of file-name on remote
machine.
status
- Show the current status of
ftp
.
struct
[struct-name
]
- Set the file transfer structure to
struct-name. By default
“stream” structure is used.
sunique
- Toggle storing of files on remote machine under unique file names. Remote
ftp server must support ftp protocol
STOU
command for successful completion.
The remote server will report unique name. Default value is off.
system
- Show the type of operating system running on the remote machine.
tenex
- Set the file transfer type to that needed to talk to TENEX machines.
trace
- Toggle packet tracing.
type
[type-name
]
- Set the file transfer
type
to
type-name. If no type is specified, the
current type is printed. The default type is network ASCII.
umask
[newmask
]
- Set the default umask on the remote server to
newmask. If
newmask is omitted, the current umask is
printed.
user
user-name
[password
]
[account
]
- Identify yourself to the remote FTP server. If the
password is not specified and the server
requires it,
ftp
will prompt the user
for it (after disabling local echo). If an
account field is not specified, and the
FTP server requires it, the user will be prompted for it. If an
account field is specified, an account
command will be 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
- Toggle verbose mode. In verbose mode, all responses from the FTP server
are displayed to the user. In addition, if verbose is on, when a file
transfer completes, statistics regarding the efficiency of the transfer
are reported. By default, verbose is on.
?
[command
]
- A synonym for help.
The following command can be used with ftpsec-aware servers.
prot
clear |
safe |
confidential |
private
- Set the data protection level to the requested level.
The following command can be used with ftp servers that has implemented the
KAUTH site command.
kauth
[principal
]
- Obtain remote tickets.
Command arguments which have embedded spaces may be quoted with quote `"'
marks.
ABORTING A FILE TRANSFER¶
To abort a file transfer, use the terminal interrupt key (usually Ctrl-C).
Sending transfers will be immediately halted. Receiving transfers will be
halted by sending a 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 will not appear until
the remote server has completed sending the requested file.
The terminal interrupt key sequence will be ignored when
ftp
has completed any local processing and
is awaiting a reply from the remote server. A long delay in this mode may
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¶
Files specified as arguments to
ftp
commands
are processed according to the following rules.
- If the file name ‘
-
’ is
specified, the stdin (for reading) or
stdout (for writing) is used.
- 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(3) with the argument supplied, and
reads (writes) from the stdout (stdin). If the shell command includes
spaces, the argument must be quoted; e.g. “" ls
-lt"”. A particularly useful example of this mechanism is:
“dir more”.
- Failing the above checks, if ``globbing'' is enabled, local file names are
expanded according to the rules used in the
csh(1); c.f. the
glob
command. If the
ftp
command expects a single local file
(.e.g. put
), only the first filename
generated by the "globbing" operation is used.
- For
mget
commands and
get
commands with unspecified local
file names, the local filename is the remote filename, which may be
altered by a case
,
ntrans
, or
nmap
setting. The resulting filename
may then be altered if runique
is
on.
- For
mput
commands and
put
commands with unspecified remote
file names, the remote filename is the local filename, which may be
altered by a ntrans
or
nmap
setting. The resulting filename
may then be altered by the remote server if
sunique
is on.
FILE TRANSFER PARAMETERS¶
The FTP specification specifies many parameters which may affect a file
transfer. The
type
may be one of
“ascii”, “image” (binary), “ebcdic”,
and “local byte size” (for PDP-10's and PDP-20's mostly).
Ftp
supports the ascii and image types of
file transfer, plus local byte size 8 for
tenex
mode transfers.
Ftp
supports only the default values for the
remaining file transfer parameters:
mode
,
form
, and
struct
.
THE .netrc FILE¶
The
.netrc file contains login and
initialization information used by the auto-login process. It resides in the
user's home directory. The following tokens are recognized; they may be
separated by spaces, tabs, or new-lines:
machine
name
- Identify a remote machine name. The
auto-login process searches the .netrc
file for a
machine
token that matches
the remote machine specified on the ftp
command line or as an open
command
argument. Once a match is made, the subsequent
.netrc tokens are processed, stopping
when the end of file is reached or another
machine
or a
default
token is encountered.
default
- This is the same as
machine
name except that
default
matches any name. There can be
only one default
token, and it must be
after all machine
tokens. This is
normally used as:
default login anonymous password
user@site
thereby giving the user automatic anonymous
ftp login to machines not specified in
.netrc. This can be overridden by using
the -n
flag to disable auto-login.
login
name
- Identify a user on the remote machine. If this token is present, the
auto-login process will initiate a login using the specified
name.
password
string
- Supply a password. If this token is present, the auto-login process will
supply the specified string if the remote server requires a password as
part of the login process. Note that if this token is present in the
.netrc file for any user other than
anonymous,
ftp
will abort the auto-login process
if the .netrc is readable by anyone
besides the user.
account
string
- Supply an additional account password. If this token is present, the
auto-login process will supply the specified string if the remote server
requires an additional account password, or the auto-login process will
initiate an
ACCT
command if it does
not.
macdef
name
- Define a macro. This token functions like the
ftp
macdef
command functions. A macro is
defined with the specified name; its contents begin with the next
.netrc line and continue until a null
line (consecutive new-line characters) is encountered. If a macro named
init
is defined, it is automatically
executed as the last step in the auto-login process.
ENVIRONMENT¶
Ftp
uses the following environment variables.
HOME
- For default location of a .netrc file,
if one exists.
SHELL
- For default shell.
SEE ALSO¶
ftpd(8)
RFC2228.
HISTORY¶
The
ftp
command appeared in
4.2BSD.
BUGS¶
Correct execution of many commands depends upon proper behavior by the remote
server.
An error in the treatment of carriage returns in the
4.2BSD ascii-mode transfer code has been corrected.
This correction may result in incorrect transfers of binary files to and from
4.2BSD servers using the ascii type. Avoid this
problem by using the binary image type.