TFTP(1) BSD General Commands Manual TFTP(1)NAMEtftp — trivial file transfer program
SYNOPSIStftp [-e] [host] [port]
DESCRIPTIONtftp 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.
The Multicast TFTP option is supported in open-loop (i.e., "slave-only")
mode based on IETF draft-dion-tftp-multicast-option-01.txt (May 2002),
which in turn was based on RFC2026.
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 a file or set of files from the specified sources. Source
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 last hostname specified
becomes the default for future transfers.
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. If
the remote-directory form is used, the remote host is assumed to
be a UNIX machine. If you need to specify IPv6 numeric address
to hosts, wrap them using square bracket like [hosts]:filename
to disambiguate the colon.
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. Multicast TFTP
was implemented by Jared D. McNeill in 2006, and first appeared in
NetBSD 4.0.
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.
BSD July 23, 2006 BSD
