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NAME

     ftp - Internet file transfer program

SYNOPSIS

     ftp [-pinegvd] [-z debug] [-z authdebug] [-z nossl] [-z certrequired]
         [-z secure] [-z verbose] [-z verify=flags] [-z cert=cert_file]
         [-z key=key_file] [-z cipher=list] [host [port]]
     pftp [-inegvd] [-z debug] [-z authdebug] [-z nossl] [-z certrequired]
         [-z secure] [-z verbose] [-z verify=flags] [-z cert=cert_file]
         [-z key=key_file] [-z cipher=list] [host [port]]

DESCRIPTION

     Ftp is the user interface to the Internet standard File Transfer
     Protocol.  The program allows a user to transfer files to and from a
     remote network site.

     Options may be specified at the command line, or to the command
     interpreter.

     -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 pftp.

     -i    Turns off interactive prompting during multiple file transfers.

     -n    Restrains ftp from attempting “auto-login” upon initial connection.
           If auto-login is enabled, ftp will check the .netrc (see netrc(5))
           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.

     -e    Disables command editing and history support, if it was compiled
           into the ftp executable. Otherwise, does nothing.

     -g    Disables file name globbing.

     -v    Verbose option forces ftp to show all responses from the remote
           server, as well as report on data transfer statistics.

     -d    Enables debugging.

     -z option
           Set SSL (Secure Socket Layer) parameters. The default is to
           negotiate via ftp protocol if SSL is available on the server side
           and then to switch it on. In this mode you can connect to both
           conventional and SSL enhanced ftpd’s.

           The SSL parameters are:

           debug       Send SSL related debugging information to stderr.

           authdebug   Enable authentication debugging.

           ssl         Negotiate SSL at first, then use ftp protocol. ftp
                       protocol negotiation goes encrypted. (Not yet
                       implemented)

           nossl, !ssl
                       switch of SSL negotiation

           certrequired
                       client certificate is mandatory

           secure      Don’t switch back to unencrypted mode (no SSL) if SSL
                       is not available.

           verbose     Be verbose about certificates etc.

           verify=int  Set the SSL verify flags (SSL_VERIFY_* in ssl/ssl.h ).

           cert=cert_file
                       Use the certificate(s) in cert_file.

           key=key_file
                       Use the key(s) in key_file.

           cipher=ciph_list
                       Set the preferred ciphers to ciph_list.  (See ssl/ssl.h
                       ).

     The client host and an optional port number 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:

     ! [command [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.

     $ 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.

     qc          Toggle the printing of control characters in the output of
                 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.

     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 -’
                 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 [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 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 [inchars [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 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).

     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.  If 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.

     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.

     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.

     1.   If the file name ‘-’ is specified, the stdin (for reading) or stdout
          (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(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”.

     3.   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.

     4.   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.

     5.   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.

ENVIRONMENT

     Ftp utilizes the following environment variables.

     HOME        For default location of a .netrc file, if one exists.

     SHELL       For default shell.

SEE ALSO

     ftpd(8), netrc(5), RFC 959

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.