Contents of the XFER.DOC file
<<<=== X F E R - DOS FILE TRANSFER UTILITY ===>>>
Version 1.50, August 15, 1986
(C) 1985, 1986 J.C. Kilday Associates
Developed at the Northern Lights BBS
Table of Contents
Introduction .................... 1
Description ..................... 1
Operating XFER .................. 2
New Features of v1.50 ........... 3
Distribution and Restrictions ... 3
Support ......................... 4
XFER v1.50 Page 1
XFER is a standalone communications utility supporting XMODEM,
XMODEM/CRC, and YMODEM file transfer operations at the DOS level on a
host PC. It is installed on a host system and may be invoked during a
communications session by a caller after being granted host system
access at the DOS level (CTTY COM1 or CTTY COM2 invoked).
This package is intended for use by BBS sysops or others who have need
for operating a "host system" remotely and performing configuration,
maintenance, or file updating/replacement functions. It facilitates
file transfers directly to/from directories which are not accessible
while using the host communications software, such as a BBS. XFER also
may be used with simpler host software packages which allow a caller
to drop to DOS (e.g., JaxHost v3.0, a shareware product available on
many BBS's as JAXHOST3.ARC). XFER will not work in local mode,
outside of a communications environment.
XFER is designed for operation on an IBM PC, XT, AT, or a close
compatible, with up to 2 communications ports (known as COM1 and COM2)
operating at 300, 1200, or 2400 bps.
On start-up, XFER searches for an "active" communications port (COM1
or COM2). If the status of COM1, is DATA SET READY and CARRIER DETECT
and a speed of 300, 1200, or 2400 bps, then XFER takes over
communications at N, 8, and 1. If COM1 is not active, it checks for
an active COM2 meeting the same criteria. If neither port is active
(meaning it was started while in local mode and no communications
active), XFER exits after printing on the would-be "host" console "NO
COMM PORT ACTIVE."
XFER may be invoked in command-line mode or in normal (menu-driven)
mode. The next section describes the syntax for invoking XFER.
Three file transfer protocols are supported as listed in the previous
section. The Ymodem implementation in XFER is noticeably faster than
that provided in many communications programs when operating at 2400
bps. The Ymodem "receive" (upload to the host) is 7%, or more, faster
than that of popular BBS software packages when running at 2400 bps on
4.77 Mhz. CPU's -- PC's or XT's. Although not supporting batch Ymodem
transfers, the Ymodem implementation in XFER is compatible with
software which sends a "Ymodem block 0" or which shifts down to
Xmodem/CRC-sized blocks at some point during the Ymodem tranfer.
XFER v1.50 Page 2
File transfer occurs to/from the default directory on the host system
or the drive/directory included in the filespec entered for the file
to be uploaded/downloaded. XFER.EXE should be located in any
directory included in the current PATH on the host system.
Command syntax for the menu-driven mode is simply:
Ignore the square brackets ( [, ] ). The optional parm ("Y" or "y")
specifies that XFER is to be initialized for conducting YMODEM
transfers only. If the Y parm is omitted, XFER is initialized to
conduct XMODEM (Checksum or CRC) transfers only.
If XFER is started without the Y parm, downloads use the XMODEM
variation the remote system is set for. XFER adjusts automatically.
XMODEM/CRC uploads, however, are specified by entering "U"; and
Checksum uploads by "C" as shown by the XFER menu. Any combination of
uploads and downloads may be performed before quitting to DOS. Return
to DOS is accomplished without loss of carrier.
Command syntax for the command-line mode is:
XFER U|D filespec [X|C|Y]
You must specify a U or a D after the command if invoking the
command-line mode; where U indicates an upload to the host system amd
D indicates download from the host system. Filespec is the full DOS
pathname and filename referring to the destination and name of a file
to be uploaded or the source and name of the file to be downloaded.
The optional parameters X, C, and Y specify the protocol to use
(Xmodem, Xmodem/CRC, and Ymodem, respectively. If none of these
characters is specified after the filespec, the default protocol of
Xmodem (checksum) is used.
XFER - Invokes menu-driven/Xmodem mode
XFER Y - Invokes menu-driven/Ymodem mode
XFER d d:\comm\JaxHost3.arc y - Invokes command-line mode to
download a file from the given
drive/directory using Ymodem
XFER U TEST.TXT - Invokes command-line mode to
upload a file to the current
(default) directory using the
default protocol - Xmodem
XFER v1.50 Page 3
Operating XFER (Continued)
Please note that entry of invalid path names and file names may
produce various error reports of the nature, "Error xx occurred in
line yyy of ... ." Every attempt has been made to trap all such error
conditions so that the program will terminate gracefully.
New Features of v1.50
The previous public version of XFER was 1.41. Version 1.50 provides
the following enhancements/new features:
- The Ymodem implementation now supports receipt of a "block 0" which
may be sent as the first block of a Ymodem upload by some programs.
No processing of this block is performed (it is discarded).
- The Ymodem implementation now supports the "step down" to 128-byte
blocks (actually 133 transmitted bytes per block) that may occur
during an upload, depending on the comm program used.
- A command-line option of invoking/operating XFER is available. For
example you may describe an upload using Ymodem to the host system
as: xfer u c:\work\foo.bar y and bypass the menu.
- And last but not least, ... this software has left the ranks of
"completely free" and public domain software products.
Distribution and Restrictions
XFER v1.50 is made available to you for private, personal use. If you
find that you have continued use for it and would like to see it
supported and enhanced, a contribution of $10 would be appreciated and
it would help with the growth of the Northern Lights BBS.
You are welcome to distribute this package to others so long as it is
unmodified and distributed in its entirety, and it is not included or
bundled with other goods or services for which a fee is charged.
Exceptions are that XFER may be distributed by bulletin boards or
other information services even though they receive fees to access
their downloadable files, or by library services so long as the fee
for the diskette on which this package is contained is not more than
Use of XFER by business entities, corporations, and government
agencies is prohibited without payment of a license fee of $15 per
installed copy (site licenses available).
XFER v1.50 Page 4
Support is available to private users who have contributed to the
well-being of the Northern Lights BBS and to business users who have
paid the appropriate license fees. This support is primarily offered
through the message base of the Northern Lights BBS which can be
reached at the number given below and on the cover page of this
documentation. Please note that support is provided only for use of
XFER on equipment for which it was designed (described earlier).
Contributions and license fees may be made payable to:
J.C. Kilday Associates
Peaks Island, ME 04108
The author, Jack Kilday, may be contacted at that address or through
the Northern Lights BBS (address messages to "Sysop") at 207-766-2467
(calls accepted at 2400 and 1200 bps and N, 8, 1).