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tftp(1)								      tftp(1)



NAME

  tftp - Provides the Trivial File Transfer Protocol (TFTP)

SYNOPSIS

  Interactive form:

  tftp [remote_host] [port]

  Command-line form:

  tftp remote_host [port] -subcommand [args]

DESCRIPTION

  The tftp command transfers files between hosts using TFTP. Because TFTP is
  a minimal file transfer protocol, the	tftp command does not provide all of
  the features described under the ftp command.	For example, tftp does not
  provide subcommands to list remote files or change directories at the
  remote host, and limited file	access privileges are given to the remote
  TFTP server. Note that the tftp command is not available when	your host is
  operating in controlled access (secure) mode.

  The remote host must have a tftpd server started by its inetd	server and
  have an account defined that limits the access of tftpd. Use the tftpd com-
  mand to set up the TFTP environment and the nobody account.

  The tftp command has two forms: interactive form and command line form.  In
  the interactive form,	tftp is	issued alone or	with a host argument that
  specifies the	default	host to	use for	file transfers during this session.
  You can also specify a port for the tftp connection to use.  When you	enter
  the interactive form,	the tftp>> prompt appears.  In the command line form,
  you specify command arguments	on the command line, and no prompt appears.
  The tftp command can overwrite a file, but prompts you before	doing so.

  When transferring data to a remote host, the transferred data	is placed in
  the directory	specified by the remote_file argument.	remote_file must be a
  fully	specified filename, and	the remote file	must both exist	and have
  write	permission set for others.  The	tftp command attempts to write the
  data to the specified	file.  However,	if the remote TFTP server does not
  have the appropriate privileges to write the remote file or if the file
  does not already exist, the transfer fails.

SUBCOMMANDS

  The tftp subcommands can be entered in either	their interactive form or in
  their	command	line form.

  ? [subcommand]

  help [subcommand]
      Displays help information.  If a subcommand is specified,	only
      information about	that subcommand	is displayed.

  ascii
      Synonym for the mode ascii subcommand.

  binary
      Synonym for the mode binary subcommand. This subcommand is used in the
      interactive mode.	 The image mode	is the same as mode binary, but	is
      used on the command line.

  blocksize value
      Sets the data block size in bytes. Specify a value in the	range 8	to
      65464. The default block size is 512 bytes. Packet size is equivalent
      to the blocksize +4 bytes	(516 bytes by default).

      The value	of blocksize is	constrained by the size	of the UDP socket
      send buffer. Before setting the block size to a large value, you should
      verify the size of the UDP socket	send buffer. This buffer has a
      default size of 9216 bytes. You can increase the buffer size by modify-
      ing the value of the udp_sendspace system	configuration parameter.
      Refer to the sys_attrs(5)	and sys_attrs_inet(5) reference	pages for
      more information on checking and setting the udp_sendspace parameter.

  connect host [port]
      Sets the remote host, and	optionally the port, for file transfers.
      Because the TFTP protocol	does not maintain connections between
      transfers, the connect subcommand	does not create	a connection to	host,
      but stores the settings for transfer operations.	Because	the remote
      host can be specified as part of the get or put subcommands, which
      overrides	any host previously specified, the connect subcommand is not
      required.

  get remote_file [local_file]

  get remote_file [remote_file ...]
      Transfers	a file or set of files from the	remote host to the local
      host.  Each of the remote_file arguments can be specified	in one of the
      following	two ways:

	+  As a	file that exists on the	remote host, if	a default host was
	   already specified.

	+  As host:file, where host is the remote host and file	is the name
	   of the file to copy to the local system.  If	this form of the
	   argument is used, the host specified	for the	last transfer becomes
	   the default host for	subsequent transfers in	this tftp session.

      In either	case, remote_file must be a fully-specified filename.

  hash
      Toggles hash marks.

  mode type
      Sets the transfer	mode to	ascii or binary.  A transfer mode of ascii is
      the default.

  octet
      Sets mode	to octet.

  put local_file [remote_file]

  put local_file [local_file...] remote_directory
      Transfers	a file or set of files from the	local host onto	the remote
      host.  The remote_directory and remote_file arguments can	be specified
      in one of	the following two ways:

	+  As a	file or	directory that exists on the remote host, if a
	   default host	was already specified.

	+  As host:remote_file,	where host is the remote host and remote_file
	   is the name of the file or directory	on the remote system.  If
	   this	form of	the argument is	used, the host specified for the last
	   transfer becomes the	default	host for subsequent transfers in this
	   tftp	session.

	   In either of	these cases, the remote	filename or directory name
	   must	be a full pathname, even if the	local and remote directories
	   have	the same name. If a remote directory is	specified, the remote
	   host	is assumed to use UNIX pathname	syntax.

  quit
      Exits tftp.  An End-of-File also exits the program.

  rate
      Displays transfer	rate information.

  rexmt	value
      Defines the retransmission time-out for each packet, in seconds.

  status
      Shows the	current	status of tftp,	including the current transfer mode
      (ascii or	binary), connection status, time-out value, and	so on.

  timeout value
      Sets the total transmission time-out to the number of seconds specified
      by value.

  trace
      Turns packet tracing on or off.

  verbose
      Turns verbose mode, which	displays additional information	during file
      transfer,	on or off.

EXAMPLES

   1.  To enter	tftp, check the	current	status,	connect	to host1, and
       transfer	the file update	from host1 to the local	host, enter:
	    $ tftp
	    tftp>> status

	    Not	connected.
	    Mode: netascii  Verbose: off    Tracing: off
	    Rexmt_interval: 5 seconds, Max-timeout: 25 seconds

	    tftp>> connect host1
	    tftp>> get /u/alice/update update
	    tftp>> quit
	    $

       The get subcommand transfers the	file update from the remote host to
       your local host.	Note that the directory	/u/alice on the	remote host
       must have read permission set for others.

       To perform the same operation in	command-line mode, enter:
	    $ tftp host1 -status -get /u/alice/update update
	    Connected to host1.
	    Mode: netascii  Verbose: off    Tracing: off
	    Rexmt_interval: 5 seconds, Max-timeout: 25 seconds


   2.  To open a tftp connection to host1, set binary mode, transfer the file
       game.exe	from the local host to host1, and rename the file in the pro-
       cess, enter:
	    $ tftp host1
	    tftp>> binary
	    tftp>> put game.exe /u/alice/tictactoe.exe

       The put subcommand transfers the	file game.exe from your	local host to
       the remote host as tictactoe.exe. Note that the directory /u/alice on
       the remote host must have write permission set for others. Also,	the
       file tictactoe.exe must already exist on	the server and have write
       permission set for others.

       To perform the same operation in	command-line mode, enter:
	    $ tftp host1 -binary -put game.exe /u/alice/tictactoe.exe


   3.  To transfer two files from the local host to two	remote hosts, enter:
	    $ tftp
	    tftp>> put product.html pricelist.html host1:/u/alice/public_html
	    tftp>> put product.html pricelist.html host2:/public/documents

       The put subcommand transfers the	files from your	local host to the
       specified directory on each remote host.	Again, the files and direc-
       tories must already exist on the	remote hosts and have write permis-
       sions set for others. When the file transfer is complete, the last
       host, host2, becomes the	default	host for subsequent transfers in this
       tftp session.

       To perform the same operation in	command-line mode, enter:
	    $ tftp host1 -put product.html pricelist.html /u/alice/public_html
	    $ tftp host2 -put product.html pricelist.html /public/documents




FILES

  /etc/hosts
      Defines the address of the local host, and specifies the names and
      addresses	of remote hosts.

  /etc/services
      Defines the sockets and protocols	used for Internet services.

SEE ALSO

  Commands:  ftp(1), ftpd(8), inetd(8),	rcp(1),	syslogd(8), tftpd(8)