TFTP(1) BSD General Commands Manual TFTP(1)NAMEtftp — trivial file transfer program
SYNOPSIStftp [-e] [host] [port]
DESCRIPTION
The tftp utility is the user interface to the Internet TFTP (Trivial File
Transfer Protocol), which allows users to transfer files to and from a
remote machine. The remote host (and optional port) may be specified on
the command line, in which case tftp uses host (and port) as the default
for future transfers (see the connect command below).
The optional -e argument sets a binary transfer mode as well as setting
the extended options as if tout, tsize, and blksize 65464, had been
given.
COMMANDS
Once tftp is running, it issues the prompt ‘tftp>’ and recognizes the
following commands:
? command-name ...
Print help information.
ascii Shorthand for mode ascii.
binary Shorthand for mode binary.
blksize blk-size
Set the tftp blksize option to blk-size octets (8-bit bytes).
Since the number of blocks in a tftp get or put is 65535, the
default block size of 512 bytes only allows a maximum of just
under 32 megabytes to be transferred. The value given for
blk-size must be between 8 and 65464, inclusive. Note that many
servers will not respect this option.
connect host-name [port]
Set the host (and optionally port) for transfers. Note that the
TFTP protocol, unlike the FTP protocol, does not maintain con‐
nections between transfers; thus, the connect command does not
actually create a connection, but merely remembers what host is
to be used for transfers. You do not have to use the connect
command; the remote host can be specified as part of the get or
put commands.
get filename
get remotename localname
get file1 file2 ... fileN
Get one or more files from the remote host. When using the host
argument, the host will be used as default host for future
transfers. If localname is specified, the file is stored
locally as localname, otherwise the original filename is used.
Note that it is not possible to download two files at a time,
only one, three, or more than three files, at a time.
To specify an IPv6 numeric address for a host, wrap it using
square brackets like “[3ffe:2900:e00c:ffee::1234]:file” to dis‐
ambiguate the colons used in the IPv6 address from the colon
separating the host and the filename.
mode transfer-mode
Set the mode for transfers; transfer-mode may be one of ascii or
binary. The default is ascii.
put file
put localfile remotefile
put file1 file2 ... fileN remote-directory
Put a file or set of files to the specified remote file or
directory. The destination can be in one of two forms: a file‐
name on the remote host, if the host has already been specified,
or a string of the form hosts:filename to specify both a host
and filename at the same time. If the latter form is used, the
hostname specified becomes the default for future transfers.
When remotename is specified, the file is stored remotely as
remotename, otherwise the original filename is used. If the
remote-directory argument is used, the remote host is assumed to
be a UNIX machine. To specify an IPv6 numeric address for a
host, see the example under the get command.
quit Exit tftp. An end of file also exits.
rexmt retransmission-timeout
Set the per-packet retransmission timeout, in seconds.
status Show current status.
timeout total-transmission-timeout
Set the total transmission timeout, in seconds.
tout Toggle the tftp "timeout" option. If enabled, the client will
pass its retransmission-timeout to the server. Note that many
servers will not respect this option.
trace Toggle packet tracing.
tsize Toggle the tftp "tsize" option. If enabled, the client will
pass and request the filesize of a file at the beginning of a
file transfer. Note that many servers will not respect this
option.
verbose Toggle verbose mode.
HISTORY
The tftp command appeared in 4.3BSD. IPv6 support was implemented by
WIDE/KAME project in 1999. TFTP options were implemented by Wasabi Sys‐
tems, Inc., in 2003, and first appeared in NetBSD 2.0.
SECURITY CONSIDERATIONS
Because there is no user-login or validation within the TFTP protocol,
the remote site will probably have some sort of file-access restrictions
in place. The exact methods are specific to each site and therefore dif‐
ficult to document here.
Files larger than 33488896 octets (65535 blocks) cannot be transferred
without client and server supporting blocksize negotiation (RFC1783).
BSD June 11, 2003 BSD
