TFTP(1) BSD General Commands Manual TFTP(1)
NAME
tftp -- trivial file transfer program
SYNOPSIS
tftp [-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 connec-
tions 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 com-
mands.
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 trans-
fers. 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 disam-
biguate 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 filename 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
Systems, 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 restric-
tions in place. The exact methods are specific to each site and therefore difficult 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