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.\"	from: @(#)ftp.1	6.18 (Berkeley) 7/30/91
.\"	$Id: ftp.1,v 1.14 2000/07/30 23:56:59 dholland Exp $
.\"
.Dd August 15, 1999
.Dt FTP 1
.Os "Linux NetKit (0.17)"
.Sh NAME
.Nm ftp
.Nd
.Tn Internet
file transfer program
.Sh SYNOPSIS
.Nm ftp
.Op Fl pinegvd
.Op Ar host
.Nm pftp
.Op Fl inegvd
.Op Ar host
.Sh DESCRIPTION
.Nm Ftp
is the user interface to the
.Tn Internet
standard File Transfer Protocol.
The program allows a user to transfer files to and from a
remote network site.
.Pp
Options may be specified at the command line, or to the
command interpreter.
.Bl -tag -width flag
.It Fl p
Use passive mode for data transfers. Allows use of ftp in environments
where a firewall prevents connections from the outside world back to
the client machine. Requires that the ftp server support the PASV
command. This is the default if invoked as
.Nm pftp.
.It Fl i
Turns off interactive prompting during multiple file transfers.
.It Fl n
Restrains
.Nm ftp
from attempting \*(Lqauto-login\*(Rq upon initial connection.
If auto-login is enabled,
.Nm ftp
will check the
.Pa .netrc
(see 
.Xr netrc 5) 
file in the user's home directory for an entry describing
an account on the remote machine.
If no entry exists,
.Nm 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.
.It Fl e
Disables command editing and history support, if it was compiled into
the
.Nm ftp
executable. Otherwise, does nothing.
.It Fl g
Disables file name globbing.
.It Fl v
Verbose option forces
.Nm ftp
to show all responses from the remote server, as well
as report on data transfer statistics.
.It Fl d
Enables debugging.
.It Fl z Ar option
Set SSL (Secure Socket Layer) parameters. The default is to negotiate
via ftp protocoll if SSL is availlable at server side and then to
switch it on. In this mode you can connect to both conventional and
SSL enhanced ftpd's.
.Pp
The SSL parameters are:
.Bl -tag -width Fl
.It Ic Ar debug
Send SSL related debugging information to stderr.
.It Ic Ar authdebug
Enable authentication debugging.
.It Ic Ar ssl
Negotiate SSL at first, then use ftp protocol. ftp protocol
negotiation goes encrypted. (Not yet implemented)
.It Ic Ar nossl, Ar !ssl
switch of SSL negotiation
.It Ic Ar certrequired
client certificate is mandatory
.It Ic Ar secure
Don't switch back to unencrypted mode (no SSL) if SSL is not available.
.It Ic Ar verbose
Be verbose about certificates etc.
.It Ic Ar verify=int
.\" TODO
Set the SSL verify flags (SSL_VERIFY_* in 
.Ar ssl/ssl.h
).
.\" TODO
.It Ic Ar cert=cert_file
.\" TODO
Use the certificate(s) in
.Ar cert_file .
.It Ic Ar key=key_file
.\" TODO
Use the key(s) in
.Ar key_file .
.It Ic Ar cipher=ciph_list
.\" TODO
Set the preferred ciphers to
.Ar ciph_list .
.\" TODO: possible values; comma-separated list?
(See 
.Ar ssl/ssl.h
).
.El
.El
.Pp
The client host with which
.Nm ftp
is to communicate may be specified on the command line.
If this is done,
.Nm ftp
will immediately attempt to establish a connection to an
.Tn FTP
server on that host; otherwise,
.Nm ftp
will enter its command interpreter and await instructions
from the user.
When
.Nm ftp
is awaiting commands from the user the prompt
.Ql ftp>
is provided to the user.
The following commands are recognized
by
.Nm ftp  :
.Bl -tag -width Fl
.It Ic \&! Op Ar command Op Ar args
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.
.It Ic \&$ Ar macro-name Op Ar args
Execute the macro
.Ar macro-name
that was defined with the
.Ic macdef
command.
Arguments are passed to the macro unglobbed.
.It Ic account Op Ar 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.
.It Ic append Ar local-file Op Ar remote-file
Append a local file to a file on the remote machine.
If
.Ar remote-file
is left unspecified, the local file name is used in naming the
remote file after being altered by any
.Ic ntrans
or
.Ic nmap
setting.
File transfer uses the current settings for
.Ic type  ,
.Ic format ,
.Ic mode  ,
and
.Ic structure .
.It Ic ascii
Set the file transfer
.Ic type
to network
.Tn ASCII .
This is the default type.
.It Ic bell
Arrange that a bell be sounded after each file transfer
command is completed.
.It Ic binary
Set the file transfer
.Ic type
to support binary image transfer.
.It Ic bye
Terminate the
.Tn FTP
session with the remote server
and exit
.Nm ftp  .
An end of file will also terminate the session and exit.
.It Ic case
Toggle remote computer file name case mapping during
.Ic mget
commands.
When
.Ic 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.
.It Ic \&cd Ar remote-directory
Change the working directory on the remote machine
to
.Ar remote-directory  .
.It Ic cdup
Change the remote machine working directory to the parent of the
current remote machine working directory.
.It Ic chmod Ar mode file-name
Change the permission modes of the file
.Ar file-name
on the remote
sytem to
.Ar mode  .
.It Ic close
Terminate the
.Tn FTP
session with the remote server, and
return to the command interpreter.
Any defined macros are erased.
.It Ic \&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
.Ic \&cr
is on (the default), carriage returns are stripped from this
sequence to conform with the
.Ux
single linefeed record
delimiter.
Records on
.Pf non\- Ns Ux
remote systems may contain single linefeeds;
when an ascii type transfer is made, these linefeeds may be
distinguished from a record delimiter only when
.Ic \&cr
is off.
.It Ic qc
Toggle the printing of control characters in the output of
.Tn ASCII
type commands.  When this is turned on, control characters
are replaced with a question mark if the output file is the
standard output.  This is the default when the standard
output is a tty.
.It Ic delete Ar remote-file
Delete the file
.Ar remote-file
on the remote machine.
.It Ic debug Op Ar debug-value
Toggle debugging mode.
If an optional
.Ar debug-value
is specified it is used to set the debugging level.
When debugging is on,
.Nm ftp
prints each command sent to the remote machine, preceded
by the string
.Ql \-\->
.It Xo
.Ic dir
.Op Ar remote-directory
.Op Ar local-file
.Xc
Print a listing of the directory contents in the
directory,
.Ar remote-directory  ,
and, optionally, placing the output in
.Ar local-file  .
If interactive prompting is on,
.Nm ftp
will prompt the user to verify that the last argument is indeed the
target local file for receiving
.Ic dir
output.
If no directory is specified, the current working
directory on the remote machine is used.
If no local
file is specified, or
.Ar local-file
is
.Fl  ,
output comes to the terminal.
.It Ic disconnect
A synonym for
.Ar close  .
.It Ic form Ar format
Set the file transfer
.Ic form
to
.Ar format  .
The default format is \*(Lqfile\*(Rq.
.It Ic get Ar remote-file Op Ar local-file
Retrieve the
.Ar 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
.Ic case  ,
.Ic ntrans ,
and
.Ic nmap
settings.
The current settings for
.Ic type  ,
.Ic form ,
.Ic mode  ,
and
.Ic structure
are used while transferring the file.
.It Ic glob
Toggle filename expansion for
.Ic mdelete  ,
.Ic mget
and
.Ic mput  .
If globbing is turned off with
.Ic glob  ,
the file name arguments
are taken literally and not expanded.
Globbing for
.Ic mput
is done as in
.Xr csh 1 .
For
.Ic mdelete
and
.Ic 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
.Ql mls remote-files \-
Note:
.Ic mget
and
.Ic mput
are not meant to transfer
entire directory subtrees of files.
That can be done by
transferring a
.Xr tar 1
archive of the subtree (in binary mode).
.It Ic hash
Toggle hash-sign (``#'') printing for each data block
transferred.
The size of a data block is 1024 bytes.
.It Ic help Op Ar command
Print an informative message about the meaning of
.Ar command  .
If no argument is given,
.Nm ftp
prints a list of the known commands.
.It Ic idle Op Ar seconds
Set the inactivity timer on the remote server to
.Ar seconds
seconds.
If
.Ar seconds
is ommitted, the current inactivity timer is printed.
.It Ic lcd Op Ar directory
Change the working directory on the local machine.
If
no
.Ar directory
is specified, the user's home directory is used.
.It Xo
.Ic \&ls
.Op Ar remote-directory
.Op Ar local-file
.Xc
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
.Ux
systems will produce
output from the command
.Ql ls \-l .
(See also
.Ic nlist . )
If
.Ar remote-directory
is left unspecified, the current working directory is used.
If interactive prompting is on,
.Nm ftp
will prompt the user to verify that the last argument is indeed the
target local file for receiving
.Ic \&ls
output.
If no local file is specified, or if
.Ar local-file
is
.Sq Fl ,
the output is sent to the terminal.
.It Ic macdef Ar macro-name
Define a macro.
Subsequent lines are stored as the macro
.Ar 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
.Ic close
command is executed.
The macro processor interprets `$' and `\e' as special characters.
A `$' 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 `\e' followed by any character is replaced by that character.
Use the `\e' to prevent special treatment of the `$'.
.It Ic mdelete Op Ar remote-files
Delete the
.Ar remote-files
on the remote machine.
.It Ic mdir Ar remote-files local-file
Like
.Ic dir  ,
except multiple remote files may be specified.
If interactive prompting is on,
.Nm ftp
will prompt the user to verify that the last argument is indeed the
target local file for receiving
.Ic mdir
output.
.It Ic mget Ar remote-files
Expand the
.Ar remote-files
on the remote machine
and do a
.Ic get
for each file name thus produced.
See
.Ic glob
for details on the filename expansion.
Resulting file names will then be processed according to
.Ic case  ,
.Ic ntrans ,
and
.Ic nmap
settings.
Files are transferred into the local working directory,
which can be changed with
.Ql lcd directory ;
new local directories can be created with
.Ql "\&! mkdir directory" .
.It Ic mkdir Ar directory-name
Make a directory on the remote machine.
.It Ic mls Ar remote-files local-file
Like
.Ic nlist  ,
except multiple remote files may be specified,
and the
.Ar local-file
must be specified.
If interactive prompting is on,
.Nm ftp
will prompt the user to verify that the last argument is indeed the
target local file for receiving
.Ic mls
output.
.It Ic mode Op Ar mode-name
Set the file transfer
.Ic mode
to
.Ar mode-name  .
The default mode is \*(Lqstream\*(Rq mode.
.It Ic modtime Ar file-name
Show the last modification time of the file on the remote machine.
.It Ic mput Ar local-files
Expand wild cards in the list of local files given as arguments
and do a
.Ic put
for each file in the resulting list.
See
.Ic glob
for details of filename expansion.
Resulting file names will then be processed according to
.Ic ntrans
and
.Ic nmap
settings.
.It Ic newer Ar file-name Op Ar local-file
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
.Ic newer  .
Otherwise, this command is identical to
.Ar get  .
.It Xo
.Ic nlist
.Op Ar remote-directory
.Op Ar local-file
.Xc
Print a  list of the files in a
directory on the remote machine.
If
.Ar remote-directory
is left unspecified, the current working directory is used.
If interactive prompting is on,
.Nm ftp
will prompt the user to verify that the last argument is indeed the
target local file for receiving
.Ic nlist
output.
If no local file is specified, or if
.Ar local-file
is
.Fl  ,
the output is sent to the terminal.
.It Ic nmap Op Ar 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
.Ic mput
commands and
.Ic put
commands issued without a specified remote target filename.
If arguments are specified, local filenames are mapped during
.Ic mget
commands and
.Ic get
commands issued without a specified local target filename.
This command is useful when connecting to a
.No non\- Ns Ux
remote computer
with different file naming conventions or practices.
The mapping follows the pattern set by
.Ar inpattern
and
.Ar outpattern  .
.Op Ar Inpattern
is a template for incoming filenames (which may have already been
processed according to the
.Ic ntrans
and
.Ic case
settings).
Variable templating is accomplished by including the
sequences `$1', `$2', ..., `$9' in
.Ar inpattern  .
Use `\\' to prevent this special treatment of the `$' character.
All other characters are treated literally, and are used to determine the
.Ic nmap
.Op Ar inpattern
variable values.
For example, given
.Ar inpattern
$1.$2 and the remote file name "mydata.data", $1 would have the value
"mydata", and $2 would have the value "data".
The
.Ar outpattern
determines the resulting mapped filename.
The sequences `$1', `$2', ...., `$9' are replaced by any value resulting
from the
.Ar inpattern
template.
The sequence `$0' is replace by the original filename.
Additionally, the sequence
.Ql Op Ar seq1 , Ar seq2
is replaced by
.Op Ar seq1
if
.Ar seq1
is not a null string; otherwise it is replaced by
.Ar seq2 .
For example, the command
.Pp
.Bd -literal -offset indent -compact
nmap $1.$2.$3 [$1,$2].[$2,file]
.Ed
.Pp
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
.Ar outpattern  ,
as in the example: `nmap $1 sed "s/  *$//" > $1' .
Use the `\e' character to prevent special treatment
of the `$','[','[', and `,' characters.
.It Ic ntrans Op Ar inchars Op Ar outchars
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
.Ic mput
commands and
.Ic put
commands issued without a specified remote target filename.
If arguments are specified, characters in
local filenames are translated during
.Ic mget
commands and
.Ic get
commands issued without a specified local target filename.
This command is useful when connecting to a
.No non\- Ns Ux
remote computer
with different file naming conventions or practices.
Characters in a filename matching a character in
.Ar inchars
are replaced with the corresponding character in
.Ar outchars  .
If the character's position in
.Ar inchars
is longer than the length of
.Ar outchars  ,
the character is deleted from the file name.
.It Ic open Ar host Op Ar port
Establish a connection to the specified
.Ar host
.Tn FTP
server.
An optional port number may be supplied,
in which case,
.Nm ftp
will attempt to contact an
.Tn FTP
server at that port.
If the
.Ic auto-login
option is on (default),
.Nm ftp
will also attempt to automatically log the user in to
the
.Tn FTP
server (see below).
.It Ic 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
.Ic mget
or
.Ic mput
will transfer all files, and any
.Ic mdelete
will delete all files.
.It Ic proxy Ar 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
.Ic proxy
command should be an
.Ic 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
.Ic proxy  :
.Ic open
will not define new macros during the auto-login process,
.Ic close
will not erase existing macro definitions,
.Ic get
and
.Ic mget
transfer files from the host on the primary control connection
to the host on the secondary control connection, and
.Ic put  ,
.Ic mput ,
and
.Ic 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
.Dv PASV
command by the server on the secondary control connection.
.It Ic put Ar local-file Op Ar remote-file
Store a local file on the remote machine.
If
.Ar remote-file
is left unspecified, the local file name is used
after processing according to any
.Ic ntrans
or
.Ic nmap
settings
in naming the remote file.
File transfer uses the
current settings for
.Ic type  ,
.Ic format ,
.Ic mode  ,
and
.Ic structure  .
.It Ic pwd
Print the name of the current working directory on the remote
machine.
.It Ic quit
A synonym for
.Ic bye  .
.It Ic quote Ar arg1 arg2 ...
The arguments specified are sent, verbatim, to the remote
.Tn FTP
server.
.It Ic recv Ar remote-file Op Ar local-file
A synonym for get.
.It Ic reget Ar remote-file Op Ar local-file
Reget acts like get, except that if
.Ar local-file
exists and is
smaller than
.Ar remote-file  ,
.Ar local-file
is presumed to be
a partially transferred copy of
.Ar remote-file
and the transfer
is continued from the apparent point of failure.
If
.Ar local-file
does not exist ftp won't fetch the file.
This command
is useful when transferring very large files over networks that
are prone to dropping connections.
.It Ic remotehelp Op Ar command-name
Request help from the remote
.Tn FTP
server.
If a
.Ar command-name
is specified it is supplied to the server as well.
.It Ic remotestatus Op Ar file-name
With no arguments, show status of remote machine.
If
.Ar file-name
is specified, show status of
.Ar file-name
on remote machine.
.It Xo
.Ic rename
.Op Ar from
.Op Ar to
.Xc
Rename the file
.Ar from
on the remote machine, to the file
.Ar to  .
.It Ic 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.
.It Ic restart Ar marker
Restart the immediately following
.Ic get
or
.Ic put
at the
indicated
.Ar marker  .
On
.Ux
systems, marker is usually a byte
offset into the file.
.It Ic rmdir Ar directory-name
Delete a directory on the remote machine.
.It Ic 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
.Ic get
or
.Ic 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
.Ic runique
will not affect local files generated from a shell command
(see below).
The default value is off.
.It Ic send Ar local-file Op Ar remote-file
A synonym for put.
.It Ic sendport
Toggle the use of
.Dv PORT
commands.
By default,
.Nm ftp
will attempt to use a
.Dv PORT
command when establishing
a connection for each data transfer.
The use of
.Dv PORT
commands can prevent delays
when performing multiple file transfers.
If the
.Dv PORT
command fails,
.Nm ftp
will use the default data port.
When the use of
.Dv PORT
commands is disabled, no attempt will be made to use
.Dv PORT
commands for each data transfer.
This is useful
for certain
.Tn FTP
implementations which do ignore
.Dv PORT
commands but, incorrectly, indicate they've been accepted.
.It Ic site Ar arg1 arg2 ...
The arguments specified are sent, verbatim, to the remote
.Tn FTP
server as a
.Dv SITE
command.
.It Ic size Ar file-name
Return size of
.Ar file-name
on remote machine.
.It Ic status
Show the current status of
.Nm ftp  .
.It Ic struct Op Ar struct-name
Set the file transfer
.Ar structure
to
.Ar struct-name .
By default \*(Lqstream\*(Rq structure is used.
.It Ic sunique
Toggle storing of files on remote machine under unique file names.
Remote ftp server must support ftp protocol
.Dv STOU
command for
successful completion.
The remote server will report unique name.
Default value is off.
.It Ic system
Show the type of operating system running on the remote machine.
.It Ic tenex
Set the file transfer type to that needed to
talk to
.Tn TENEX
machines.
.It Ic trace
Toggle packet tracing.
.It Ic type Op Ar type-name
Set the file transfer
.Ic type
to
.Ar type-name  .
If no type is specified, the current type
is printed.
The default type is network
.Tn ASCII .
.It Ic umask Op Ar newmask
Set the default umask on the remote server to
.Ar newmask  .
If
.Ar newmask
is ommitted, the current umask is printed.
.It Xo
.Ic user Ar user-name
.Op Ar password
.Op Ar account
.Xc
Identify yourself to the remote
.Tn FTP
server.
If the
.Ar password
is not specified and the server requires it,
.Nm ftp
will prompt the user for it (after disabling local echo).
If an
.Ar account
field is not specified, and the
.Tn FTP
server
requires it, the user will be prompted for it.
If an
.Ar 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
.Nm ftp
is invoked with \*(Lqauto-login\*(Rq disabled, this
process is done automatically on initial connection to
the
.Tn FTP
server.
.It Ic verbose
Toggle verbose mode.
In verbose mode, all responses from
the
.Tn 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.
.It Ic ? Op Ar command
A synonym for help.
.El
.Pp
Command arguments which have embedded spaces may be quoted with
quote `"' marks.
.Sh 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
.Dv 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
.Dv ABOR
processing.
If the remote server does not support the
.Dv ABOR
command, an
.Ql ftp>
prompt will not appear until the remote server has completed
sending the requested file.
.Pp
The terminal interrupt key sequence will be ignored when
.Nm 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
.Nm ftp
program must be killed by hand.
.Sh FILE NAMING CONVENTIONS
Files specified as arguments to
.Nm ftp
commands are processed according to the following rules.
.Bl -enum
.It
If the file name
.Sq Fl
is specified, the
.Ar stdin
(for reading) or
.Ar stdout
(for writing) is used.
.It
If the first character of the file name is
.Sq \&| ,
the
remainder of the argument is interpreted as a shell command.
.Nm Ftp
then forks a shell, using
.Xr 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.
\*(Lq" ls -lt"\*(Rq.
A particularly
useful example of this mechanism is: \*(Lqdir more\*(Rq.
.It
Failing the above checks, if ``globbing'' is enabled,
local file names are expanded
according to the rules used in the
.Xr csh  1  ;
c.f. the
.Ic glob
command.
If the
.Nm ftp
command expects a single local file (.e.g.
.Ic put  ) ,
only the first filename generated by the "globbing" operation is used.
.It
For
.Ic mget
commands and
.Ic get
commands with unspecified local file names, the local filename is
the remote filename, which may be altered by a
.Ic case  ,
.Ic ntrans ,
or
.Ic nmap
setting.
The resulting filename may then be altered if
.Ic runique
is on.
.It
For
.Ic mput
commands and
.Ic put
commands with unspecified remote file names, the remote filename is
the local filename, which may be altered by a
.Ic ntrans
or
.Ic nmap
setting.
The resulting filename may then be altered by the remote server if
.Ic sunique
is on.
.El
.Sh FILE TRANSFER PARAMETERS
The FTP specification specifies many parameters which may
affect a file transfer.
The
.Ic type
may be one of \*(Lqascii\*(Rq, \*(Lqimage\*(Rq (binary),
\*(Lqebcdic\*(Rq, and \*(Lqlocal byte size\*(Rq (for
.Tn PDP Ns -10's
and
.Tn PDP Ns -20's
mostly).
.Nm Ftp
supports the ascii and image types of file transfer,
plus local byte size 8 for
.Ic tenex
mode transfers.
.Pp
.Nm Ftp
supports only the default values for the remaining
file transfer parameters:
.Ic mode  ,
.Ic form ,
and
.Ic struct  .
.Sh ENVIRONMENT
.Nm Ftp
utilizes the following environment variables.
.Bl -tag -width Fl
.It Ev HOME
For default location of a
.Pa .netrc
file, if one exists.
.It Ev SHELL
For default shell.
.El
.Sh SEE ALSO
.Xr ftpd 8 ,
RFC 959
.Sh HISTORY
The
.Nm ftp
command appeared in
.Bx 4.2 .
.Sh BUGS
Correct execution of many commands depends upon proper behavior
by the remote server.
.Pp
An error in the treatment of carriage returns
in the
.Bx 4.2
ascii-mode transfer code
has been corrected.
This correction may result in incorrect transfers of binary files
to and from
.Bx 4.2
servers using the ascii type.
Avoid this problem by using the binary image type.