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Version 17.32 TurboDial 2.33 Universal Line Printer Edition
ZCOMM User Manual 31
8. YOUR TELEPHONE DIRECTORY
ZCOMM's telephone directory is a big flexibility advantage over
traditional communications programs which require one or more separate
files for each system called, or limit directory information to little
more than a telephone number.
The telephone directory is a plain ASCII text file which can be edited
with standard text editors (brief, teco, EMACS, edlin, etc.).
Normally, ZCOMM expects to find the telephone directory in the file
/PHODIR.t on the current disk. The pathname may be changed with the
DOS environment variable PHONES. Forward slashes should be used to
indicate directories.
EXAMPLE: C>set PHONES=c:/yam/lib/PHODIR.t
The putsnp program may also be used to change ZCOMM's default, as
described above.
The call command is normally used to make a connection with another
computer. When you give a call name command, ZCOMM prepares for a
modem call and then searches the telephone directory file for a line
starting with name.
It is not necessary to type the entire name as it appears in the file.
ZCOMM will find the first entry that name is a prefix of.
EXAMPLE: call cis would access either the cis300 or cis1200 telephone
directory entry, whichever was first.
When using two entries with similar names (such as "cis300" and
"cis1200"), place the favorite entry first. This way you can just
type call cis to get the desired entry.
If the search is successful, the call command copies the complete
directory entry name to the remote string parameter, where it can be
used for log entries and automatic password generation. ZCOMM
executes the commands on the rest of the line (if any), and on
succeeding lines beginning with a space or tab.
There is no arbitrary limit to the size of the telephone directory.
Popular entries may be placed near the front to minimize searching
time. Scripts can also be placed in separate files when desired.
8.1 Customizing Your Telephone Directory
Your next step is to edit the distribution PHODIR.t to suit your
needs.
When ZCOMM begins execution, it searches the telephone directory for
(C) 1988 Omen Tech Inc Chapter 8 Your Telephone Directory
Version 17.32 TurboDial 2.33 Universal Line Printer Edition
ZCOMM User Manual 32
the setup entry. (A directory entry has the entry name starting at
the left margin.)
The setup telephone directory in the distributed phodir.t file invokes
a demonstration menu. Once you have exercized the various
demonstration possibilities, search for the xsetup telephone directory
and change it to setup be removing the "x". This will blank out the
oroginal setup entry which appears later in the file.
setup port 1
The first line of the "setup" entry selects port 1.
: if !c speed 1200 putw "ATZ\r"
This line is commented out with a colon (:). If the colon is removed,
the speed is changed to 1200 and ZCOMM sends an initialization command
to the modem if no carrier detect signal is present. If a carrier
detect signal is present (modem still connected to the remote
computer), the speed is not changed, and no initialization command is
sent to the modem.
pd1; pz480
enables incoming time/date information provided by the ZMODEM and True
YMODEM protocols. Time/date stamping of transmitted files provides
many advantages over traditional protocols, including the ability to
selectively transmit files if the source file is newer than receiver's
copy. The number in the pz480 command should represent the local time
zone expressed as minutes behind GMT.[1]
This line should be commented out with a leading colon (or removed) if
you use a backup program that depends on the dates of files to
determine which to save.
set mprefix "ATDP"
sets the string parameter mprefix to ATDP, setting the Hayes modem to
use rotary (pulse) dialing. If your phone uses tone dialing, comment
that line out (place a leading colon to make ZCOMM pass over it) and
uncomment the line containig "ATDT".
set l "1"; set m "1"
__________
1. Pacific Standard Time is 480 minutes behind Greenwich Mean Time
(C) 1988 Omen Tech Inc Chapter 8 Your Telephone Directory
Version 17.32 TurboDial 2.33 Universal Line Printer Edition
ZCOMM User Manual 33
The l and m string parameters support the dynamic selection of one or
more ALDS alternate long distance carriers. The default values for
these parameters is the digit 1.
When making entries in your telephone directory, use %l- for numbers
with different area codes, and %m- for numbers with the same area code
as yours.
The set command sets the string parameter l (lower case L) to 1
(number), providing for normal long distance access. If you have an
alternative long distance service, set this parameter to the required
access string for that service.[2] The "set m 1" command sets the
string parameter m to 1, providing for normal long distance access for
numbers in your same area code. If you have an alternative long
distance service, set this parameter to the required access string for
that service, plus your area code if required. (Some alternate long
distance services require the area code for all calls, even those in
your own area code.)
set answerback "YOUR NAME CITY\r\n\21"
Change the answerback setting to reflect your name.[3] Be sure to keep
the \21 at the end of the string.[4]
The next lines configure soft keys F3 to FS4. Their functions are
described at the end of Chapter 15.
: display bell=visual
Causes bell characters to be displayed as a non spacing flashing
musical note instead of sounding. If you want a silent bell,
uncomment this line.
set quitcmd "\003\336off\r"
This string is sent to the remote before disconnecting when an ALT-Q
is typed during a protocol file transfer.
: set calllog c:/calllog
: set rxlog c:/tmp/rxlog
: set txlog c:/tmp/txlog
__________
2. Use the "setsavenet" entry in PHODIR.t as a prototype.
3. Some timesharing systems may require a specific answerback string.
4. See Chapter 23 for a description character escapes.
(C) 1988 Omen Tech Inc Chapter 8 Your Telephone Directory
Version 17.32 TurboDial 2.33 Universal Line Printer Edition
ZCOMM User Manual 34
The above lines set the pathnames for logs of calls, files received,
and files transmitted. The above log file entries must be commented
out for use with ZCOMM.
set f10 "@help"
if fyamhelp.t set helpfile "yamhelp.t"
if f/umanh.hlp set helpfile "@yhp /umanh.hlp"
if fumanh.hlp set helpfile "@yhp umanh.hlp"
The above lines locate the help file and program F10 to summon the
help processor if available. These lines may be changed if you keep
these files in other directories.
: if dc ps4 pn2 pr97
If a color display is used, these colors may be more suitable than the
default black and white. Uncommenting this line selects red status
line (ps4), green normal text (pn2), and a blue/yellow for reverse
video (pr97). Another possibility is "pn3" which selects blue-green
for normal text. You may wish to experiment with these values to find
ones best suited for your particular combination of display equipment
and visual preferences. Changing the colors from time to time may
prolong display tube life. The colors Telephone Directory entry
displays the colors generated by the possible numeric parameter
values:
EXAMPLE: gosub colors
Some programs, including the "DEC Store" demonstration, will not
display exactly as intended with some combinations of the above
display parameters.
If you use a long distance credit card or sometimes dial out from
hotel or PBX lines, be sure to modify the att, ddd, hotel9, and hotel8
telephone directory entries to suit your needs.
You may wish to keep your phone numbers etc. in one file and relegate
information specific to each computer to a separate file. The setup
entry checks for the existience of a PHONES.TS file and executes it of
found.
set s0 ""
setc pho "%PHONES\&s"; if f%pho source %pho
if %s0 return
The supplied PHONES.TS file is used on Omen's 386 Xenix system, and
may be used as an example. If you use VT100 emulation with keyboard
mapping most of the time, you can add the contents of the keyboard
mapping file MK.STD or MK.101 to your PHONES.TS file.
While editing your telephone directory, you might wish to add some
(C) 1988 Omen Tech Inc Chapter 8 Your Telephone Directory
Version 17.32 TurboDial 2.33 Universal Line Printer Edition
ZCOMM User Manual 35
entries for your favorite systems in the same format used by the
"amrad", "amsat", or "denver" directory entries.
When the PHODIR.t file is ready, type "ZCOMM<ENTER>" to run ZCOMM.
ZCOMM will print several lines of greeting and then silently execute
the commands in the "setup" directory entry.
If ZCOMM can't open PHODIR.t, exit ZCOMM with "x<ENTER>" and copy
PHODIR.t to the correct directory, or set the DOS PHONES environment
variable to the actual pathname (see Chapter 14). Also check that the
DOS CONFIG.SYS files contains FILES=20 to allow ZCOMM a sufficient
number of open files for proper script operation. If using DOS 3.x,
you will need to have a STACKS line in your CONFIG.SYS file, as
described in Chapter 26.
(C) 1988 Omen Tech Inc Chapter 8 Tutorial Introduction
Version 17.32 TurboDial 2.33 Universal Line Printer Edition
ZCOMM User Manual 36
9. HANDS ON TUTORIAL
As a first order of business, run the demonstration program by typing
ZCOMMDEMO at the DOS prompt. The demo asks certain questions about
your system, and then allows you to exercise a few of ZCOMM's features
from a menu. It's a good way to get a first "feel" for ZCOMM before
getting down to business with the industrial strength software you
will be using.
Remember to turn off the CAPS LOCK key when running ZCOMM.
ASSUMPTIONS: In addition to the minimum hardware requirements for
ZCOMM, this tutorial assumes the use of a Hayes Smartmodem 1200 (or
equivalent) connected to the COM1 port in accordance with the
instructions in Chapter 7. The tutorial assumes that ZCOMM.EXE,
YHP.EXE, UMANH.HLP, and PHODIR.t are copied to the root directory of
your working disk, and that ZCOMM.EXE has been serialized with the
putsnp program. If your system configuration is different, you will
have to read the manual carefully to learn how to adjust for your
configuration.
After typing ZCOMM from the DOS prompt to load ZCOMM, type F10 to
activate the flash-up help processor. Browse through it briefly to
familiarize yourself with the information available via the F10 help
key.
To make a call without using a directory entry, type speed 1200 (or
whatever) and then the phone number:
speed 1200 123-4567
The modem then dials the number. When you are connected, ZCOMM will
return to its command prompt. Keyboard F2 to begin talking with the
remote. Give some commands to the remote until several screens' worth
of text have scrolled by.
Now press the PgUp function key. The screen will now display text
that had scrolled off before. Use the PgUp, Home, PgDn, and End
function keys to move around in the review buffer.
Look for a moderately interesting nugget of wisdom, and use the up
arrow and down arrow function keys on the numeric keypad to place the
interesting part at the top of the screen.
Hit "t" to set the top marker. This causes all the text to display in
high intensity. Now move down using the down arrow key to place the
first line of unwanted text at the top of the screen.
Hit the "b" key to set the bottom pointer. This will change the
displayed text back to normal intensity.
(C) 1988 Omen Tech Inc Chapter 9 Tutorial Introduction
Version 17.32 TurboDial 2.33 Universal Line Printer Edition
ZCOMM User Manual 37
Now hit "w" and ZCOMM will prompt for a filename to write the selected
text to. Type the filename followed by <ENTER>, and ZCOMM will write
the selected data. When the write operation is finished, the screen
will redisplay the text.
When you have the feel of it, type F1 to return to the term function
and conversational connection to the remote computer.
The demonstration disk circular buffer search/cut/paste menu choice
demonstrates many of the review subcommands.
Next, log off the remote computer. When it drops the line, ZCOMM
displays "No Carrier Detect Signal" in reverse video to announce that
the connection has been lost. At this time you are still in the term
function.
When you return to ZCOMM's command prompt (by typing F1), type
"off<ENTER>" to disconnect the modem and exit back to DOS.
Now is a good time to read the rest of the manual to discover the
power of ZCOMM. Chapter 9 presents some unusual sessions
demonstrating more of ZCOMM's capabilities.
9.1 Sample Sessions
Direct connection to COM2 at 19kb
unix port 2 speed 19200 source mk.101; t
| | | |
| | | Map keyboard, Invoke term function
| | ___ Set 19200 bits per second
| ______________ Select port COM2
_________________________ System name
Typical bulletin board
rcpm port 1 speed 1200 123-4567 t -8g
| | | | |
| | | | _ Term function, graphics
| | | _______ Number to call
| | __________________ 1200 baud
| _________________________ Select COM1
____________________________________ System name
A Not so Typical Session
The example below assumes a Hayes modem connected to a radio receiver
tuned to the W1AW ASCII bulletins. Refer to a recent issue of QST
Magazine for a W1AW schedule. to select the best signal. Usually,
the error rate is lowest when receiving a strong signal near the
Maximum Useable Frequency (MUF). Set the radio for Upper Sideband
(C) 1988 Omen Tech Inc Chapter 9 Sample Sessions
Version 17.32 TurboDial 2.33 Universal Line Printer Edition
ZCOMM User Manual 38
(USB) reception. Tune it so the resulting audio frequencies make the
RD (Received Data) light turn on about 50 percent of the time. Reset
the modem by powering it down before attempting regular calls.
w1aw speed 110 putw "ATS10=255 C0 H2 D\r" t -v
| | |
| | -v prints control chars
| | as ^C so they won't
| | erase the screen, etc.
| Ignore Carrier Detect, Carrier Off, Special Off
| Hook (Don't close relay), Originate, Online
|________ W1AW ASCII transmissions are at 110 bps
A>ZCOMM call unix Connect to a local system named unix
jabber jabber ... Login to system, change directory
<ALT-2>Command: Get a ZCOMM command prompt
sz prg?.? prghlp.mm Upload some files
jabber jabber ...
sz *.c *.h Download some source files
Receiving ... ZMODEM AutoDownload accepts them
kermit -ix Start the Unix Kermit server
<F1>>>>c: Get ZCOMM's command prompt
remote dir Get a directory listing
Directory... Directory listing on screen
get f2 Get (fetch) a file
f2 Open ... File arrives
send myfile Send myfile to server
finish Finish server access
t Enter term function
kermit send f1 Start a Kermit file transfer
f1 Open... File is received AUTOMAGICALLY!
jabber jabber ... Log off local system
<F1>>>>c: Get ZCOMM's command prompt
port 1 Select modem on COM1
call rcpm Dial a system called "rcpm"
jabber jabber ... Keyboarding with remote
<Home> Review function at top of text
/to superhacker Search for beginning of message to you
t Set top pointer
/to j. fred muggs Search for beginning of next message
b Set bottom pointer
w Write selected text to a disk file
<F1> Return to term function
E<ENTER> Tell the rcpm to enter a message
<ALT-2>Command: Get a ZCOMM command prompt
open -p letter Open "letter" and send to bbs, using
prompt and throttle modes to slow
transmission so the remote system won't
drop characters.
dir Find out what files are on the RCPM
xmodem s foo.bqr Command RCPM to download a file
(C) 1988 Omen Tech Inc Chapter 9 Sample Sessions
Version 17.32 TurboDial 2.33 Universal Line Printer Edition
ZCOMM User Manual 39
<ALT-2>Command: Get a ZCOMM command prompt
rc foo.bqr Download a file with XMODEM/CRC
PgUp PgUp ... Flip back to the first part of
directory previously listed
<ENTER> Back to term function
xmodem s dr.who Download a critical file
<ALT-2>Command: Get a ZCOMM command prompt
rc \misc\dr.who Download the file
jabber jabber ... More keyboarding, logoff
<F1>>>>c: Get ZCOMM's command prompt
Connect the modem to the radio's audio and tune in W1AW
create rtty.tmp Create a disk file for the bulletins
call w1aw
bleep twort sneep Static on the radio - pure line hits until
W1AW is received while sending ASCII
<F2>k Review/k command clears the buffer
QST DE W1AW ...
END ... AR
<ALT-C> Close the capture file
<F1>>>>c:off Return to DOS
(C) 1988 Omen Tech Inc Chapter 9 Accessing Computer Systems
Version 17.32 TurboDial 2.33 Universal Line Printer Edition
ZCOMM User Manual 40
10. ACCESSING COMPUTER SYSTEMS
10.1 Dialing
Once you modem is interfaced per Chapter 7, you can connect to a
remote system with the call command referencing an entry in your
telephone directory entry.
EXAMPLE: call kgbvax
If a telephone directory entry has not been set up, TurboLearn(TM) may
be invoked to dial a phone number and then learn your login procedure
by keyboarding the F4 key. You may choose to add the resulting script
to your telephone directory, or retain it as a separate file acessible
with the source command. Please refer to the learn command in Chapter
15.
If you just want to call a number without ZCOMM learing anything, type
the telephone number from the command prompt already.[1]
EXAMPLE: 123-4567
When the modem connects, ZCOMM returns to the command prompt. You can
then keyboard the F2 key to connect your keyboard to the remote
system. If you wish to use "bulletin board graphics", keyboard t -8g
instead.
10.2 Telenet/PC-Pursuit
For best results, identify with D1 when Telenet asks for your terminal
type. This selection prevents the network from adding padding
characters, which are just a waste of time with ZCOMM.
To use XMODEM, YMODEM, Telink, and other traditional protocols on PC
Pursuit, give the Telenet command
SET 1:0,4:2,5:0,7:8,12:0
after connecting to the PC-Pursuit target city. This command prevents
Telenet from "eating" control characters or breaking the connection
when files containing certain patterns are transmitted. This command
disables Telenet's "<ENTER>@<ENTER>" escape.
To use ZMODEM or Kermit Sliding Windows give the command:
__________
1. You may wish to add the /mnp modifier described in Chapter 7.
(C) 1988 Omen Tech Inc Chapter 10 Accessing Computer Systems
Version 17.32 TurboDial 2.33 Universal Line Printer Edition
ZCOMM User Manual 41
SET 4:2,5:1,12:1
instead.
Please refer to Chapter 13 for network flow control considerations.
10.3 Tymnet
If using Tymnet, type Ctrl-R Ctrl-X just before the host computer name
to enable flow control with XOFF and XON. "Half Duplex" may be
activated with Ctrl-H. Check with your network's documentation for
further details or updates to this information.
(C) 1988 Omen Tech Inc Chapter 10 File Names
Version 17.32 TurboDial 2.33 Universal Line Printer Edition
ZCOMM User Manual 42
11. FILE NAMES Good and Bad
The pathnames of downloaded files must be legal PC-DOS file names as
described in The File Specification in chapter 2 of the PC-DOS manual.
When choosing file names, remember that PC-DOS does not distinguish
between uppercase and lowercase characters in pathnames.
The Compuserve-B, ZMODEM, YMODEM, and Kermit protocols use pathnames
generated by the sending program. File names transmitted from other
systems may not be legal for DOS, or they may reference directories
that cannot be created.[1]
When ZCOMM receives a pathname from the sending program, ZCOMM first
checks for the existence of a file with the same name. If no such
file is found, ZCOMM attempts to open the named file for writing.
Missing directories are generated automatically. A pathname that
cannot be opened for reading or writing is considered illegal.
EXAMPLE: foo..bar is illegal for DOS because it contains two dots.
An Illegal pathname is translated to name.NNN where name is the
filename portion of the given file name restricted to 8 characters,
and NNN is an assigned three digit number starting with 001 and
incremented after each file download. If a file with this new name
already exists, the number is incremented up to 999, until a unique
file name is found. The open fails if a unique number cannot be
found.
EXAMPLE: A downloaded file with the name newprog.patch.1 might
actually be downloaded as newprog.001.
This check for illegal file names is made whenever ZCOMM attempts to
create an output file.
EXAMPLE: t foo.bar.baz given from the command prompt would invoke file
name translation.
11.1 Pathname Translations
Files affected by the dirrx and dircx string variables have their
directory paths and/or device specifier stripped if the string
variable ends in a "/". Otherwise a file specification with an
absolute path overrides the string variable. The pathname of the
__________
1. A cirectory cannot be created if a regular file with the same
pathname is present.
(C) 1988 Omen Tech Inc Chapter 11 File Names
Version 17.32 TurboDial 2.33 Universal Line Printer Edition
ZCOMM User Manual 43
incoming file is checked before any of these transformations, allowing
a host system to place all files received with a protocol in a private
directory.
EXAMPLE: C>set DIRRX=C:/download
places files received with a protocol in the download directory on
drive C unless the file specification included an absolute path or
device letter.
dirrx File Stored Location
(empty) any (same)
C:/a f C:/a/f
C:/a /f /f
C:/a A:f A:f
C:/a/ f C:/a/f
C:/a/ /f C:/a/f
C:/a/ A:f C:/a/f
SV Affected commands
dirrx r{bcotwx7}, fget, get, bdump, usq, ZMODEM/Kermit
AutoDownload
dirsx s{bctx7}, send, B protocol sends[2]
dircx create, t, message, private, >, bro/a
review/w, ap[d] (2nd argument)
dirfx f, open
To show the possible pathname translations, consider the pathmame:
A:/spy/kgb/sabotage/666 sent between two copies of ZCOMM with the
ZMODEM protocol.
The sending program command: sz A:/spy/kgb/sabotage/666 sends the
file name 666.
The command sz -f A:/spy/kgb/sabotage/666 sends the complete
pathname /spy/kgb/sabotage/666.
The command sz ONAME=hogwash A:/spy/kgb/sabotage/666 sends the
pathname hogwash.
sz PREFIX=C:/fbi/security/intelligence A:/spy/kgb/sabotage/666
sends the pathname C:/fbi/security/intelligence/666. Note that a disk
identifier (C:) is being sent.
__________
2. If the dirsx parameter is set, ambiguous or wild card file names
cannot be used.
(C) 1988 Omen Tech Inc Chapter 11 File Names
Version 17.32 TurboDial 2.33 Universal Line Printer Edition
ZCOMM User Manual 44
On reception with ZMODEM AutoDownload or the rz command, the last
example (C:/fbi/security/intelligence/666) would normally be stored
under that exact pathname, creating the directories C:/fbi,
C:/fbi/security, and C:/fbi/security/intelligence if needed.
If the dirrx string variable had contained C:/downloads the incoming
drive specifier would still have overidden the dirrx specification.
If the dirrx string variable had contained C:/ollie/to_do/ the file
would have ended up as C:/ollie/to_do/666 to the consternation of all.
The command rz foobar could have been used to rename this file to
foobar in the current directory.
The oncloserx and onclosetx string parameters may be used to specify
commands to execute after each file received or sent with file
transfer protocols. Their use is described in Chapter 11.
(C) 1988 Omen Tech Inc Chapter 11 Protocol File Transfers
Version 17.32 TurboDial 2.33 Universal Line Printer Edition
ZCOMM User Manual 45
12. PROTOCOL FILE TRANSFERS
With many different ways to transfer files with ZCOMM, your choice of
file transfer methods could make the difference between efficient,
error free data and slow or error prone transfers. This chapter gives
an overview of the different ways to transfer files with emphasis on
their relative merits.
A file transfer protocol should have high integrity (assurance of
accurate data) and high robustness (low probability of aborting a
transfer). When the file transfer is attended, robustness is not so
critical because the transfer can be restarted.
The following subchapters discuss these file transfer methods in more
detail.
12.1 ZMODEM
ZMODEM was developed for the public domain under contract by Telenet,
a major packet switched network. ZMODEM has been submitted to the
ANSI X12C committee.
ZMODEM provides a greatly simplified user interface. The file name is
entered once, and transfer options may be given to the sending
program, even those that apply to the receiver. ZMODEM
AutoDownload(TM) allows menu and mouse driven programs to download
files and commands with no extra keyboarding required.
ZMODEM transfers one or more files with a single command. The size
and transfer time for each file is displayed, and the total number of
files, size, and transmission time is displayed when more than one
file remains to be sent on a command.
Keyboarding ALT-F allows the receiver to bypass an individual file
without having to restart the batch.
ZMODEM transfers both files and commands. Command download allows one
of the computers to take positive control of the session. A security
challenge (activated by ZMODEM AutoDownload(TM)) guards against Trojan
Horse messages.*
ZMODEM file transfers preserve the file date[1] and the exact file
contents, unlike traditional protocols that append garbage to files.
In a sense, ZMODEM is four file transfer protocols in one. Streaming
__________
1. Controlled by the d and z numeric parameters
(C) 1988 Omen Tech Inc Chapter 12 Protocol File Transfers
Version 17.32 TurboDial 2.33 Universal Line Printer Edition
ZCOMM User Manual 46
transmission provides full throughput over satellite links and packet
switched networks. One of three ZMODEM streaming control methods may
be used with systems that allow the sender to monitor the received
data for error correction packets without interrupting transmission.
Individually acknowledged packets support other systems.
ZMODEM allows programs to adjust the protocol parameters for optimum
efficiency as the file is being sent.
Some programs support ZMODEM compression for even faster file
transfers under appropriate conditions with the Z file transfer
option.
ZMODEM is immune to most of the error conditions that prevent accurate
file transfers with traditional protocols.
+ ZMODEM data transfers are protected by the Federal Standard 32 bit
CRC to assure reliable transfers. This 32 bit CRC gives an
undetected error rate five orders of magnitude better than XMODEM's
16 bit CRC, and more than a billion times better than checksum
XMODEM. ZMODEM uses 16 bit CRC for file transfers with programs
that do not support 32 bit CRC.
+ Most important, all ZMODEM protocol transactions are protected by
CRC. Competing protocols advertising 16 or 32 bit CRC sometimes
fail under stress because critical control messages are not
protected by CRC.
ZMODEM supports Intelligent Crash Recovery(TM) and advanced file
management. If you've ever been disconnected when a huge file
transfer was almost finished, you'll appreciate resuming/recovering
the file transfer with the ZMODEM r option.
You can use the ZMODEM n option to transfer only those files that have
changed since the last time they were transferred. With the p option,
you can unconditionally protect files that already exist on the
destination system. To update only the files you already have while
skipping the rest, use the Yn options.
To send a file with ZMODEM, the command sz file1 can be given from
either the main command prompt, or from the term function via a
secondary command prompt obtained with ALT-2. Multiple files and wild
cards may be used.
EXAMPLE: sz file1 file2 *.lst
12.1.1 ZMODEM AutoDownload If Z mode has been enabled (the default),
ZCOMM's term function will detect a ZMODEM transmission and receive
the file(s) automatically, after a security check. File transfer
options for ZMODEM automatic downloads may be specified with the
(C) 1988 Omen Tech Inc Chapter 12 Protocol File Transfers
Version 17.32 TurboDial 2.33 Universal Line Printer Edition
ZCOMM User Manual 47
adlopts string parameter.
The rz command may be also given from a command prompt.
Please refer to the sz and zcommand commands described in Chapter 15
for examples and information.
Rz and sz programs for Unix and VAX/VMS are available in rzsz.zoo.
12.1.2 Tuning ZMODEM Parameters Chapter 21.2 describes a number of
ZMODEM numeric parameters which may be adjusted for extraordinary
situations, or to fine tune the last 0.1 per cent of possible
performance.
The ZMODEM subpacket length (zmodem L parameter) and the ZMODEM frame
length (zmodem l parameter) deserve special mention. People tend to
confuse these with the familiar 128 and 1024 byte block length used in
XMODEM transfers.
When a ZMODEM frame length of 0 is specified (the default), a single
frame will span the entire file if there are no errors. This is the
main source of ZMODEM's reputation for fast transfers.
Setting the ZMODEM frame length to a number between 64 and 16384
restricts the frame length to that value. At the end of each frame,
the sender stops sending and waits for an acknowledgement from the
receiver. When set, the ZMODEM frame length corresponds in function
to the 128 or 1024 byte block length of XMODEM based protocols.
Each ZMODEM frame consists of one or more subpackets of 32 to 1024
bytes. Since the subpackets within a frame are sent without pause, a
short subpacket length does not exact the terrible throughput penalty
associated with short XMODEM and Kermit blocks. In the absence of
transmission errors, a 256 byte subpacket length has about two per
cent more overhead than a 1024 byte subpacket length. However, the
longer subpacket length does increase error recovery time.
ZCOMM dynamically adjusts the ZMODEM subpacket length on the basis of
transmission speed and observed error rate. If you know what the
error rate on a particular call will be before starting a ZMODEM file
transfer, setting the zmodem L numeric parameter will provide a small
but noticeable improvement in performance, with 1024 best for clean
lines and smaller numbers better for noisy lines.
When sending files over noisy phone lines not involving networks, the
speed of error recovery may be increased by decreasing the values of
the ZMODEM t and p numeric parameters.
Fascinating information about ZMODEM and other protocols is provided
in ymodem.doc and zmodem.doc, part of yzmodem.zoo (yzmodem.arc).
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12.1.3 Manual ABORT If for some reason a ZMODEM transfer fails,[2]
the program on the remote machine may be manually terminated by
repeatedly typing Ctrl-X characters at it until the program exits.
12.2 XMODEM Family Protocols
12.2.1 TRUE YMODEM(TM) Developed in 1981, YMODEM extensions to
XMODEM are finding their way into many communications programs. Rb
and sb programs are available for Unix and VAX/VMS. With Omen's
Enhanced Data Recovery(TM), YMODEM gives excellent efficiency,
integrity, and good robustness in many applications.
True YMODEM transfers one or more files in a batch without alteration
or added garbage characters. True YMODEM preserves the file date
across multiple time zones. ZCOMM and the Unix(TM) rb and sb programs
and ZCOMM preserve the file modification date.[3]
12.2.2 YMODEM-1k The sb k option (1024 byte blocks) may be used to
enhance throughput, especially when using timesharing systems,
satellite links, or packet networks that can support the longer
blocks.
EXAMPLE: sb -k *.c *.h sends all .c and .h files in the current
directory with 1024 byte blocks.[4]
YMODEM and YMODEM-1k transfers can be received with the rb or F3
commands.
YMODEM file transfers with Unix and VMS systems are discussed later in
this chapter.
A few obsolete programs claiming to support YMODEM actually use XMODEM
with 1024 byte blocks; use ZCOMM's sx -k and rx XMODEM commands with
these non conforming products.
12.2.3 YMODEM with OverThruster YMODEM and YMODEM-1k file
downloading from networks and timesharing systems is slowed by
response times. This slowing may be significant even when 1k blocks
__________
2. For example, Disk Full or NUKE
3. Controlled by the d and z numeric parameters
4. ZCOMM switches to 128 byte blocks at the end of a file when the
length warrants.
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are used. With some systems, one can speed up YMODEM downloads by
using the o option with the rb command to receive the file. Because
OverThruster(TM) defeats error recovery, a line hit will usually abort
a download. OverThruster(TM) may be used with X.PC or MNP error
correcting link level protocols.
EXAMPLE: rb -o
SEE ALSO: O numeric parameter
12.2.4 XMODEM-1k The XMODEM-1k protocol transfers one file per
command with 1024 byte blocks and a nominal 16 bit CRC. The file name
must be entered for both the sender and the receiver. Programs
lacking ZCOMM's Cybernetic Data Recovery(TM) logic are less likely to
transfer data accurately under marginal conditions. XMODEM's use of
every possible 8 bit code limit its effectiveness in many
applications.
The end of the file may be padded by up to 127 or 1023[5] garbage
characters.
To send a file with XMODEM-1k: sx -k file1
To receive a file with XMODEM-1k: rc file1
12.2.5 XMODEM-CRC (with fallback) The XMODEM-CRC protocol transfers
one file per command. The XMODEM-CRC protocol requires the receiving
program to initiate an XMODEM-CRC transfer.
The file name must be entered for both the sender and the receiver.
Even with CRC-16, programs lacking ZCOMM's Cybernetic Data
Recovery(TM) are less likely to transfer data under marginal
conditions. XMODEM-CRC's short data blocks and use of every possible
8 bit code limit its effectiveness in many applications.
The end of the file may be padded by up to 127 garbage characters.
To send a file with XMODEM (or XMODEM-CRC): sx file1
To receive a file with XMODEM-CRC: rc file1
12.2.6 Classic XMODEM The original MODEM protocol, developed by Ward
Christensen, is supported by a large and growing number of programs
operating on a variety of micros and minis. The base level XMODEM
__________
5. Some programs (including ZCOMM) limit this padding to 127 bytes.
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protocol gives good results when used over low error rate direct
telephone connections. XMODEM's short data blocks and use of every
possible 8 bit code preclude its application in many environments.
File transfers with this protocol add up to 127 garbage characters to
transferred files. The XMODEM protocol can transfer one file per
command. The file name must be entered at both the sender and the
receiver.
To send a file with XMODEM: sx file1
To receive a file with Classic XMODEM: rx file1
12.2.7 Relaxed XMODEM ZCOMM's XMODEM and YMODEM support has been
optimized for maximum reliability with a wide variety of systems under
a wide variety of conditions.
The default XMODEM and YMODEM timeout limits approach typical
"relaxed" timings and rarely need to be lengthened except under the
most sluggish of conditions. The zmodem t, T, and p numeric
parameters (q.v.) control timeouts for XMODEM, YMODEM, and ZMODEM.
The default values allow 10 seconds for a packet to appear and a
maximum 5 second pause within a packet before starting error recovery.
EXAMPLE: zmodem pt200 pp150 :: Set more relaxed X/Y/ZMODEM
timing
Omen Technology does not recommend tightening these timings for XMODEM
and YMODEM transfers on noisy lines.
12.2.8 XMODEM with OverThruster XMODEM file downloading from
networks and timesharing systems is slowed by short blocks and long
response times. With some systems, one can speed up downloads by
using the ro command to receive the file. Because OverThruster(TM)
defeats error recovery, a line hit will usually abort a download.
With nearly error free connections, one can save enough time from the
increased throughput to make up for the failed transfers.
OverThruster(TM) may be used with X.PC or MNP error correcting link
level protocols.
EXAMPLE: ro file1
EXAMPLE: rb -o
SEE ALSO: O numeric parameter
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12.2.9 YMODEM-g: Traditional Overdrive The proliferation of error
correcting modems has sparked a proliferation of YMODEM-g programs,
more and more of which actually meet minimal YMODEM protocol
specifications.
YMODEM-g transmits 0 or more files per batch with an ACK-less variant
of YMODEM-1k. The sender does not wait for individual data blocks to
be acknowledged, allowing high speed transfers with error correcting
modems.
YMODEM-g assumes an error free communications channel. A single
transmission error or character lost because of DOS or TSR interrupt
latency ruins the entire transfer, and YMODEM-g does not support Crash
Recovery(TM).
ZCOMM supports True YMODEM-g with the sb and rb -g commands.
EXAMPLE: sb *.old Sends files in the current directory with YMODEM or
YMODEM-g protocol. The receiver controls whether YMODEM or YMODEM-g
is used for the transfer.
EXAMPLE: rb -g Receives with YMODEM-g protocol.
12.2.10 XMODEM Mutants Misrepresented as YMODEM Despite continuing
education efforts, a few lazy software providers insist on identifying
their mutant XMODEM protocols as "ymodem". They choose to ignore the
definition of YMODEM that Ward Christensen wrote when he coined the
term YMODEM in his April 1985 message:
(a) a record 0 containing filename date time and size
(b) a 1K block size option
(c) CRC-16.
In case of questions, please refer to ymodem.doc, part of yzmodem.zoo
(yzmodem.arc) for for the official YMODEM protocol.
12.2.11 Qmodem-G/Streaming XMODEM The Qmodem program and certain
bulletin boards provide an ACKless XMODEM mutant protocol selected
with the Qmodem G protocol menu choice.
The sx and rx -g commands support this mutant XMODEM.
EXAMPLE: rx -g qmodem.fil
12.2.12 WXMODEM (People-Link) ZCOMM supports WXMODEM protocol
downloads with the rw command. On the People-Link timesharing
service, WXMODEM downloads are faster than XMODEM downloads.
Throughput, reliability, accuracy, and amenities are not as good as
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ZMODEM or SuperKermit, but neither of these protocols are currently
available on that system. WXMODEM adds up to 127 garbage bytes to
transferred files. Omen Technology does not recommend WXMODEM for use
over noisy phone lines.
EXAMPLE: rw file1
12.2.13 MODEM7 Batch The MODEM7 batch protocol passes CP/M file
names from the sending program to the receiver one character at a
time. The compatibility, throughput, and reliability problems of this
kluge prompted the development of YMODEM. Nonetheless, when it
becomes necessary to transfer files with a program lacking more
advanced protocols, MODEM7 batch is better than nothing.
File names transmitted with the MODEM7 batch protocol must obey the
restrictions of both 8 bit CP/M and DOS. The f option cannot be used
with MODEM7 batch. Data transfer within MODEM7 batch uses XMODEM
protocol, and all of XMODEM's weaknesses discussed above apply to
MODEM7 batch. MODEM7 batch does not preserve the modification date or
exact file contents.
EXAMPLE: s7 file1.ext *.baz sends files with MODEM7 batch.
EXAMPLE: r7 receives one or more files with MODEM7 batch.
12.2.14 Telink/FIDO The Telink protocol expands upon the MODEM7
batch kluge with a specially formatted block containing the length of
the file and the local DOS time and date. The length data allows the
receiver to truncate the file length to that the original file. All
of the MODEM7 batch compatibility and reliability problems apply to
Telink.[6] The zmodem Z numeric parameter or the z file transfer
option may be used to correct the time/date stamping of files
transferred between different time zones.
EXAMPLE: zmodem pZ120; st file1.ext *.baz Sends the specified files
with a 2 hour time zone adjustment.
EXAMPLE: rt -z60 Receives one or more files with a 60 minute time zone
adjustment.
__________
6. ZCOMM's rt and st commands were verified with Minitel 3.0 by Tom
Jenning's Fido Software; other Programs may not produce the same
results.
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12.2.15 SEAlink When transferring files with the CLINK 1.13
compatible programs, ZCOMM's rb and sb commands recognize SEAlink's
modified Telink protocol. The rb command allows a transmitting
SEAlink program to use sliding windows. Telink time zone and file
name considerations apply to SEAlink. In addition, because SEAlink
uses all 256 of the possible 8 bit codes for both data transfer and
protocol management, some modems and networks that operate with XMODEM
will not accommodate SEAlink. As with the MODEM7 and Clink protocols
mentioned above, the SEAlink protocol is included for convenience in
situations where the YMODEM and ZMODEM protocols are not
implemented.[7]
EXAMPLE: zmodem pZ120; sb file1.ext *.baz Sends the specified files
to a SEAlink program with a 2 hour time zone adjustment.
EXAMPLE: rb -z60 Receives one or more files from a SEAlink program
with a 60 minute time zone adjustment.
12.3 Kermit
Kermit operates with a wide range of computer systems, including those
whose restrictive terminal interfaces prevent XMODEM transfers.
Kermit uses an encoding technique called quoting to represent control
characters and (if necessary) parity bits with standard printable
characters. It is one of the few asynchronous error correcting
protocols that work properly with half duplex IBM front ends. Because
of the overhead from character quoting, Kermit is less efficient
(slower) than the ZMODEM.
Kermit can transfer one or more files per command, preserving the
exact file length. The popular timesharing service The Source
supports the Kermit file transfer protocol in ASCII and binary modes.
Kermit was developed at Columbia University. The protocol and
supporting mainframe programs are described in documents available
from Columbia University and elsewhere.
12.3.1 Incompatible Kermit Dialects When sending files with the
Kermit Protocol, ZCOMM uses all 8 bits for the transfer unless a 7 bit
parity mode (e.g., ena -7e) is used, the kermit 7 numeric parameter is
__________
7. ZCOMM's SEAlink was verified with CLINK 1.13 by Systems
Enhancement Associates. Other Programs may not produce the same
results because of ambiguities in the SEAlink documentation and
undocumented protocol variants.
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non zero, or the other program requests 8th bit qouting. If ZCOMM is
using a 7 bit parity mode (such as ena -7m), ZCOMM requests 8th bit
quoting unless the kermit 8 numeric parameter is non zero.
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Both programs must use the same parity
for Kermit file transfers to succeed.
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Kermit does not provide an automatic means of forcing both the sender
and receiver to use the same dialect. Files cannot be transferred if
the two programs disagree on parity handling, Such failures are quite
commonplace. A common symptom is a transfer that starts up normally
but always fails at the same block. Setting appropriate parity
corrects these Kermit failures.
ZCOMM's Kermit AutoDownload(TM) (enabled with the K mode) allows the
term function to sense the beginning of a Kermit file download, make
the proper determination on whether to use 8 bit serial data, and
execute the file download without user intervention.
12.3.2 Kermit Performance Enhancements Super-Kermit (Kermit with
Sliding Windows) transmits up to 31 packets before waiting for a
response, increasing throughput with timesharing systems and networks.
ZCOMM uses sliding windows and CRC error detection if the other
machine's Kermit supports them.
ZCOMM also supports long packets for increased throughput with
suitable systems, including many that do not support sliding windows.
ZCOMM allows Kermit long packets up to 1000 characters on DOS, up to
2048 on 32 bit Unix systems.
The maximum send packet length is set by the kermit l numeric
parameter. ZCOMM will ask for sliding windows if this is set to 94 or
less.
EXAMPLE: k pl94
The maximum receive packet length is set by the kermit L numeric
parameter. ZCOMM will ask for sliding windows if this is set to 94 or
less.
EXAMPLE: k pL94
With the default values for the kermit l and kermit L parameters,
ZCOMM will choose long packets over sliding windows when a choice is
possible.
ZCOMM supports 12 bit Kermit checksums and 16 bit Kermit CRC for
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professional error detection performance. ZCOMM uses the most
reliable Kermit error correction available. Shorter checksums may be
forced by changing the kermit b numeric parameter.
EXAMPLE: kermit sb file1 file2
EXAMPLE: kermit rb
12.3.3 ZCOMM Kermit Capabilities At a Glance
Local operation..................Yes
Remote operation.................Yes
Transfers text files.............Yes
Transfers binary files...........Yes
Wildcard send....................Yes
Filename collision avoidance.....Yes
Can time out.....................Yes
8th-bit prefixing................Yes
8 bit serial data................Yes
Sliding Windows..................Yes
Long Packets.....................Yes
Repeat count prefixing...........Yes
Alternate block checks...........Yes
Terminal emulation...............Multiple
Communication settings...........Yes
Transmit BREAK...................Yes
IBM mainframe communication......Yes
Transaction logging..............Yes
Act as server....................no
Talk to server...................Yes
Advanced commands for servers....Yes
Handle file attributes...........no
Programmable reset string........Yes
12.3.4 Accessing Kermit Servers The commands to start up a Kermit
server vary from system to system. Unix C-Kermit can be started in
server mode with kermit -ix given to Unix or VMS. When the Kermit
server is active, the ZCOMM get, send, and remote ... commands may be
used. The ZCOMM finish command causes the remote Kermit server to
exit to its operating system.
12.3.5 Kermit Caveats If the Kermit protocol doesn't work with IBM
mainframe communications, incorrect ASCII/EBCDIC translate tables may
be the problem.
Some mainframe "front ends" require special characters or a break
signal to recover from transmission errors ("line hits"). The
kermreset string parameter (q.v.) may be programmed with the required
sequence.
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SEE ALSO: kermreset string parameter
Some versions of Kermit translate files as they are sent. Typical
modifications include CR/LF to NL transformations and CPMEOF
stripping. When transferring binary files, such editing must be
disabled with SET FILE TYPE BINARY or similar commands given to the
other program. The demonstration in Chapter 9 includes several Kermit
server access and file transfer commands.
When downloading files from some versions of Kermit, best results may
sometimes be obtained by starting ZCOMM's kermit receive before typing
the carriage return that starts the sender on the remote. If the
other program includes an adjustable initial delay, you can save time
by setting it to zero.
SEE ALSO: kermit d numeric parameter
SEE ALSO: K mode (Kermit AutoDownload(TM))
12.4 Uploading Files to Remote Unix Systems
On Unix(TM) systems, files may be uploaded most conveniently and
efficiently with the ZMODEM protocol supported by the Unix rz program.
The rz program supports a subset of ZCOMM's ZMODEM features; see the
rz program's manual page for more information.
If rz is not installed on the Unix system, unpack the rzsz.zoo file[8]
with: looz -e rzsz.zoo given from the DOS prompt.[9] Next, the command
source zupl.t calls the zupl.t script to upload the bootstrap file
minirb.c, compile it, and use it to upload the remainder of the source
files.
After the rest of the files have been uploaded, compile rz.c and sz.c
using the directions given in the README file and in the C source
files.
The manual "pages" rz.1 and sz.1 may be formatted with nroff commands
such as
nroff -Tlp -man rz.1 sz.1
Versions of sq, type, usq, and zoo are available for Unix. The Unix
__________
8. This file is part of the DSZ and Professional-YAM distributions.
9. The rzsz.zoo or rzsz.arc file is also available on TeleGodzilla
and other bulletin boards.
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version of USQ has a -n flag to strip carriage returns. In addition,
the undos program may be used to remove carriage returns from Unix
files.
12.5 Downloading Files from Remote Unix Systems
To download files from Unix(TM) systems, simply use the Unix sz
program to send the desired files to ZCOMM. To Unix keyboard:
sz file ... ZCOMM's ZMODEM AutoDownload(TM) takes care of the rest
for you, saving unnecessary keystrokes.
If one or more of the files already exists on the destination disk,
use sz -y file ... instead, to replace the old copies on your
computer.
Another useful option sends only the files that exist on both
computers (Y), and furthermore sends only those that are newer (n):
sz -Yn file ...
When files are long and transmission slow, you can save time by
squeezing them first with sq. Source for a Unix compatible version of
sq is available in xsq.cq. The zoo program, available for DOS and
Unix, may also be used to compress file(s) before transmission.
Omen Technology products support ZMODEM compression with the Z option.
All Omen Technology products support compression by Run Length
Encoding (RLE). Unix flavors of Professional-YAM also support LZW
compression.
Unix source files normally do not contain carriage returns used by
CP/M and DOS. Some CP/M or DOS programs, such as C compilers, do not
require carriage returns in the source files. Others, such as the
Microsoft Macro Assembler, become quite confused by such files,
although such files fully meet the requirements of the ASCII standard.
Carriage Returns may be added before downloading with the todos or
tocpm programs. Carriage returns may be added during the transfer
with the sz a option. Carriage Returns may be added after the
transfer by some program editors, including uEMACS. (Other editors,
such as DOS edlin may crash trying to edit such files.) Short files
(less than 28kb) may be converted using ZCOMM's read and create
commands to pass the data through ZCOMM's capture buffer.
Text files may also be downloaded using the capture buffer if sz has
not been installed on the Unix machine.
If a file or set of files are to be transported between two Unix
systems, it may be helpful to place them in a tar or cpio archive (and
possibly squeeze the archive) before transmission. This procedure
will preserve the Unix file modes and modification times, and bypass
pathname restrictions imposed by DOS.
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12.6 VMS File Transfers
The abovementioned rz and sz sources also compile on the DEC VMS C
compiler. Instructions for compiling, linking, and installing the
programs are contained in the rz.c and sz.c source files.
Most of the comments made above about Unix file transfers apply to VMS
as well.
The command source vupl.t calls the vupl.t script to upload the files
needed to compile the programs on VMS. The script attempts to invoke
a Kermit server and use Kermit to upload the files. If no Kermit
server is found, the script uses the DCL create command to upload the
files by emulating a paper tape reader.
Make certain to "install" the VMS sz command to the DCL interpreter.
12.7 CompuServe File Transfers
ZCOMM supports CompuServe Quick-B and the faster Extended Quick-B (B+)
file transfer protocols.
As this is being written, these protocols are being revised. Please
check the newest.me file for possible changes.
B Protocol is used by the CompuServe Timesharing Service through the
CompuServe, Tymnet, and Telenet networks. B Protocol file transfers
are initiated by the CompuServe computer. The B Protocol file
transfer protocol is well supported by this timesharing service.
Under typical conditions, the B Protocol saves 35 per cent or more in
file transmission time and connect charges compared to XMODEM protocol
transfers.
The c or C mode must be set with ena -c or ena -C to allow the B
protocol to seize control and transfer files.
The adlopts string parameter allows the y and v file transfer options
to be specified for CIS-B transfers.
The w numeric parameter controls the block length used by the
CompuServe B Protocol. A longer length increases throughput, but may
overload some networks, resulting in excessive retransmissions or
failed transfers. With the new Extended Quick-B protocol, the maximum
block length is 1024 data bytes. A value of 0 (the default) allows
the Compuserve computer to control the block length, up to 1024 with
Extended Quick-B.
A negative value controls the upload block length but still allows
Compuserve to control the download block length (1024 with Extended
Quick B).
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Uploads to Compuserve using longer block lengths are especially
sensitive to poor flow control, especially when error correcting
modems (MNP, etc.) are used. If B protocol uploads fail or require
excessive retransmissions, correct the flow control arrangements,
disable the modem's error correction, or try a smaller upload block
size.
The data contents of successfully transferred file(s) are not affected
by this parameter.
Some networks may garble data when Quick-B's streaming causes ZCOMM to
respond to incoming data concurrently with incoming data. The o
numeric parameter can be set to 0 to disable streaming (send-ahead).
It is essential to use the same interface speed to the modem as the
modem's transmission rate when uploading files with B protocol. If
the modem buffers any characters, ZCOMM's response to CompuServe's
flow control will be too slow to prevent loss of data.
The CompuServe B Protocol controls all file transfer operations
(except permission to overwrite files) from the timesharing system.
Waiting for long files to download can be boring. You can start the
transfer and walk away from the computer, but CompuServe will stay
connected for 15 minute$ after the transfer is finished if you don't
come back when the download finishes. This expense can be avoided by
typing ALT-Q once the protocol transfer has started. ALT-Q tells
ZCOMM to disconnect as soon as the protocol transfer is completed,
stopping the connect charges. An alternative method is to control the
transfers with a script, using either ejryam or the less sophisticated
cissig and dow.t scripts included with the software distribution.
When "browsing" through CompuServe's software "downloading section"
libraries, the kcisdl.t script file and ZCOMM allow you to download a
file with a single keystroke: F3. Installation instructions are
provided in that file.
12.8 BIX File Transfers
BIX (Byte Information Exchange) supports ZMODEM, YMODEM, XMODEM-1k,
and Kermit file transfers.
The Tymnet phone number in the bix telephone directory entry should be
changed for your calling area. Other scripts are provided to handle
BIX mail and conferences.
When setting up a new BIX account, give the command call bix,new to
force a login to the BIX new account program.
Use "join listings" to get the current, properly functioning version
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of the BIX file transfer software. Be sure to select ZMODEM downloads
and Kermit (sliding windows) uploads with the "OPTIONS" menu choice.
Their transfer time predictions are about 40 per cent too pessimistic
for ZMODEM transfers.
12.9 User Exit Processing
User exits are available for additional processing after each file is
transferred.
The oncloserx string parameter may be used to perform user commands or
call a script once for each file received with a file transfer
protocol.
EXAMPLE: set oncloserx "@crc %rname; !%mv %rname /tmp"
When each file is received, the crc command calculates and displays a
CRC for the file, and the !% command calls the mv program to move the
file just received to the /tmp directory.
The onclosetx string parameter may be used to perform user commands or
call a script once for each file sent with a file transfer protocol.
Wild card file name expansions may not be used.
EXAMPLE: The following causes each successfully sent file to be moved
to the /done directory.
set onclosetx
@if !d? !%mv %rname /done
SEE ALSO: rname, tname, drive, pwd string parameters, ?, d? test
conditions
NOTE: User exits may cause protocol timeouts if their execution takes
too long.
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