ftpd(3tcl) Tcl FTP Server Package ftpd(3tcl)
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NAME
ftpd - Tcl FTP server implementation
SYNOPSIS
package require Tcl 8.3
package require ftpd ?1.3?
::ftpd::server ?myaddr?
::ftpd::config ?option value? ?option value ...?
fsCmd append path
fsCmd delete path channel
fsCmd dlist path style channel
fsCmd exists path
fsCmd mkdir path channel
fsCmd mtime path channel
fsCmd permissions path
fsCmd rename path newpath channel
fsCmd retr path
fsCmd rmdir path channel
fsCmd size path channel
fsCmd store path
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DESCRIPTION
The ftpd package provides a simple Tcl-only server library for the FTP
protocol as specified in RFC 959 (http://www.rfc-edi-
tor.org/rfc/rfc959.txt). It works by listening on the standard FTP
socket. Most server errors are returned as error messages with the ap-
propriate code attached to them. Since the server code for the ftp
daemon is executed in the event loop, it is possible that a bgerror
will be thrown on the server if there are problems with the code in the
module.
COMMANDS
::ftpd::server ?myaddr?
Open a listening socket to listen to and accept ftp connections.
myaddr is an optional argument. myaddr is the domain-style name
or numerical IP address of the client-side network interface to
use for the connection.
::ftpd::config ?option value? ?option value ...?
The value is always the name of the command to call as the call-
back. The option specifies which callback should be configured.
See section CALLBACKS for descriptions of the arguments and re-
turn values for each of the callbacks.
-authIpCmd proc
Callback to authenticate new connections based on the ip-
address of the peer.
-authUsrCmd proc
Callback to authenticate new connections based on the
user logging in (and the users password).
-authFileCmd proc
Callback to accept or deny a users access to read and
write to a specific path or file.
-logCmd proc
Callback for log information generated by the FTP engine.
-fsCmd proc
Callback to connect the engine to the filesystem it oper-
ates on.
-closeCmd proc
Callback to be called when a connection is closed. This
allows the embedding application to perform its own
cleanup operations.
-xferDoneCmd proc
Callback for transfer completion notification. In other
words, it is called whenever a transfer of data to or
from the client has completed.
CALLBACKS
authIpCmd callback
The authIpCmd receives the ip-address of the peer attempting to
connect to the ftp server as its argument. It returns a 1 to al-
low users from the specified IP to attempt to login and a 0 to
reject the login attempt from the specified IP.
authUsrCmd callback
The authUsrCmd receives the username and password as its two ar-
guments. It returns a 1 to accept the attempted login to the
ftpd and a 0 to reject the attempted login.
authFileCmd callback
The authFileCmd receives the user (that is currently logged in),
the path or filename that is about to be read or written, and
read or write as its three arguments. It returns a 1 to allow
the path or filename to be read or written, and a 0 to reject
the attempted read or write with a permissions error code.
logCmd callback
The logCmd receives a severity and a message as its two argu-
ments. The severities used within the ftpd package are note,
debug, and error. The logCmd doesn't return anything.
fsCmd callback
The fsCmd receives a subcommand, a filename or path, and op-
tional additional arguments (depending on the subcommand).
The subcommands supported by the fsCmd are:
fsCmd append path
The append subcommand receives the filename to append to
as its argument. It returns a writable tcl channel as its
return value.
fsCmd delete path channel
The delete subcommand receives the filename to delete,
and a channel to write to as its two arguments. The file
specified is deleted and the appropriate ftp message is
written to the channel that is passed as the second argu-
ment. The delete subcommand returns nothing.
fsCmd dlist path style channel
The dlist subcommand receives the path that it should
list the files that are in, the style in which the files
should be listed which is either nlst or list, and a
channel to write to as its three arguments. The files in
the specified path are printed to the specified channel
one per line. If the style is nlst only the name of the
file is printed to the channel. If the style is list
then the file permissions, number of links to the file,
the name of the user that owns the file, the name of the
group that owns the file, the size (in bytes) of the
file, the modify time of the file, and the filename are
printed out to the channel in a formatted space separated
format. The dlist subcommand returns nothing.
fsCmd exists path
The exists subcommand receives the name of a file to
check the existence of as its only argument. The exists
subcommand returns a 1 if the path specified exists and
the path is not a directory.
fsCmd mkdir path channel
The mkdir subcommand receives the path of a directory to
create and a channel to write to as its two arguments.
The mkdir subcommand creates the specified directory if
necessary and possible. The mkdir subcommand then prints
the appropriate success or failure message to the chan-
nel. The mkdir subcommand returns nothing.
fsCmd mtime path channel
The mtime subcommand receives the path of a file to check
the modify time on and a channel as its two arguments.
If the file exists the mtime is printed to the channel in
the proper FTP format, otherwise an appropriate error
message and code are printed to the channel. The mtime
subcommand returns nothing.
fsCmd permissions path
The permissions subcommand receives the path of a file to
retrieve the permissions of. The permissions subcommand
returns the octal file permissions of the specified file.
The file is expected to exist.
fsCmd rename path newpath channel
The rename subcommand receives the path of the current
file, the new file path, and a channel to write to as its
three arguments. The rename subcommand renames the cur-
rent file to the new file path if the path to the new
file exists, and then prints out the appropriate message
to the channel. If the new file path doesn't exist the
appropriate error message is printed to the channel. The
rename subcommand returns nothing.
fsCmd retr path
The retr subcommand receives the path of a file to read
as its only argument. The retr subcommand returns a
readable channel that the specified file can be read
from.
fsCmd rmdir path channel
The rmdir subcommand receives the path of a directory to
remove and a channel to write to as its two arguments.
The rmdir subcommand removes the specified directory (if
possible) and prints the appropriate message to the chan-
nel (which may be an error if the specified directory
does not exist or is not empty). The rmdir subcommand
returns nothing.
fsCmd size path channel
The size subcommand receives the path of a file to get
the size (in bytes) of and a channel to write to as its
two arguments. The size subcommand prints the appropri-
ate code and the size of the file if the specified path
is a file, otherwise an appropriate error code and mes-
sage are printed to the channel. The size subcommand re-
turns nothing.
fsCmd store path
The store subcommand receives the path of a file to write
as its only argument. The store subcommand returns a
writable channel.
closeCmd
The closeCmd receives no arguments when it is invoked, and any
return value it may generate is discarded.
xferDoneCmd sock sock2 file bytes filename err
The xferDoneCmd receives six arguments when invoked. These are,
in this order, the channel handle of the control socket for the
connection, the channel handle of the data socket used for the
transfer (already closed), the handle of the channel containing
the transfered file, the number of bytes transfered, the path of
the file which was transfered, and a (possibly empty) error mes-
sage. Any return value it may generate is discarded.
VARIABLES
::ftpd::cwd
The current working directory for a session when someone first
connects to the FTPD or when the REIN ftp command is received.
::ftpd::contact
The e-mail address of the person that is the contact for the ftp
server. This address is printed out as part of the response to
the FTP HELP command.
::ftpd::port
The port that the ftp server should listen on. If port is spec-
ified as zero, the operating system will allocate an unused port
for use as a server socket; afterwards, the variable will con-
tain the port number that was allocated.
::ftpd::welcome
The message that is printed out when the user first connects to
the ftp server.
::ftpd::CurrentSocket
Accessible to all callbacks and all filesystem commands (which
are a special form of callback) and contains the handle of the
socket channel which was active when the callback was invoked.
BUGS, IDEAS, FEEDBACK
This document, and the package it describes, will undoubtedly contain
bugs and other problems. Please report such in the category ftpd of
the Tcllib Trackers [http://core.tcl.tk/tcllib/reportlist]. Please
also report any ideas for enhancements you may have for either package
and/or documentation.
When proposing code changes, please provide unified diffs, i.e the out-
put of diff -u.
Note further that attachments are strongly preferred over inlined
patches. Attachments can be made by going to the Edit form of the
ticket immediately after its creation, and then using the left-most
button in the secondary navigation bar.
KEYWORDS
ftp, ftpd, ftpserver, rfc 959, services
CATEGORY
Networking
tcllib 1.3 ftpd(3tcl)