tftp(1) - NetBSD Manual Pages

TFTP(1)                 NetBSD General Commands Manual                 TFTP(1)


NAME

     tftp -- trivial file transfer program


SYNOPSIS

     tftp [-e] [host] [port]


DESCRIPTION

     tftp 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.

NetBSD 7.1.2                     July 23, 2006                    NetBSD 7.1.2