www.pudn.com > pccp047.zip > MANUAL

 
 
		  Pete Cann's Communication Package 
 
	    Portions Copyright (C) 1992 Peter Edward Cann 
 
	     (Please see the file README for legal junk) 
 
This is a set of programs and data files for communication between a 
PC and something external, possibly over a modem. It is drastically 
different from most other communications programs, in that it is 
highly modular and generally requires the user to write batch files 
and/or scripts to make use of it. This is what you might call a 
"hacker style" paradigm (not to be confused with "cracker", generally 
an infantile individual who feels so insignificant that they screw 
other people in a desperate attempt to feel powerful). Hackers are 
people who are very comfortable with computers, and like to have a 
lot of control and to know what's going on. The source code for all 
of these programs is included in the distribution, so if you know C 
you have all the information I do now. 
 
All of the programs give USAGE: information if invoked without 
arguments. All of the programs that use a port can use COM 1 through 
8, but COM 5 and 6 are only for AT and later machines and have not 
been tested. 
 
The centerpiece of the package is TERM. This is a terminal emulator. 
It takes an emulation file, which you create or modify with EMUED. 
EMUED lets you specify strings to send for any programmable key, and 
lets you enter strings of characters and substitution tokens to 
invoke functions. These would be the "escape sequences", although 
they need not begin with Escape. The token codes are in EMU.H. The 
emulation facility also provides a graphics character substitution 
table for graphics character commands. TERM and EMUED look in the 
directory named by the PCCPPATH environment variable for emulation 
files, if PCCPPATH is set. The program CCODES types a hex listing of 
display character codes for use when assigning graphics characters in 
EMUED. 
 
TERM generates a CRLF in response to a Linefeed character, so it is 
often desirable to program an emulation to do a DOWN in response to a 
Linefeed. For LF insertion, the function CRLF can be performed in 
response to a CR. If the emulation file basename is prefixed with a 
plus sign (+), local echo is activated. 
 
The program TERMPLAY will step a file through an emulation. 
 
The program MASTERM invokes term with the three or four arguments, 
but if you exit TERM you get a menu for file transfers or beginning a 
dribble file. The file transfer programs are three variations on 
XMODEM in each direction, and have fairly clear names. 
 
The program SESSION is a simple host program, for use AFTER password 
validation by the script facility. It is hard-coded for 8n1 bits. It 
expects the modem to be in AT&C1 mode, that is, Carrier Detect 
conveys information. The last (optional) two arguments to SESSION are 
directories for download and upload. If they are given, they are 
prepended to the entered pathname in file transfer operations. If a 
directory is given, dot-dot (..) is prohibited in pathnames and the 
Shell option is not available. 
 
The environment of any subschell contains REMOTE=YES, so you can do 
 
	IF NOT "%REMOTE%"=="YES" THING 
 
in a batch file, where THING is something that would be bad to do 
from a comport, such as run a display editor. SESSION terminates if 
Carrier Detect goes false, unless it is running the shell. 
 
The program MESSIN accepts a message from the port and appends it to 
the specified file. This is for email to the sysop. The program 
MESSOUT asks for a filename in the specified directory and displays 
it with pagination. Security is achieved through sparse naming. 
 
The program COMSCRPT runs scripts. It is very powerful, with multiple 
branching look-fors, timeouts and retry limits. 
 
The script file must have the extension ".SCR". If the PCCPPATH 
environment variable is set, the program looks for the script there. 
The program loads the script into RAM and then executes it. Lines are 
limited to 80 characters. The number of lines is limited to 512. 
 
The characters '|' and '~' are special. '|' means CR in < lines and > 
lines (LF is stripped for > processing); and newline in ! lines. '~' 
means 0.4 second delay in < lines and bell in ! lines. (In > lines it 
means itself.) Also, in < and > lines, `xx (backquote followed by two 
hex digits) expands to the specified character code. Letters in the 
hex number may be either case. There is no validity checking. Also in 
< lines, ^ means break. To send a magic character, use its hex code 
with a backquote. 
 
The first line of the script file is the first three arguments as for 
TERM, space-delimited. In subsequent lines, the first character of 
each line is the command; the rest of the line (after the delimiting 
space) is argument(s). A final string argument may include spaces, 
and begins after the delimiting space. Blank lines are ignored. 
 
The command characters are as follows: 
 
; 
	{introduces comment; line ignored; space not required} 
 
:  
	{label for conditional or unconditional goto}  
 
g  
	{goto label #} 
 
*  
	{establishes a demon to goto label upon Control-X from keyboard} 
	{* -1 cancels} 
 
r    
	{increments specified retry register} 
	{zeros register and goes to label if register > retries} 
	{register is 0 - 255} 
 
0  
	{zeros the specified retry register} 
 
p  
	{processes pending look-fors; falls through upon timeout} 
	{clears pending look-for list upon completion} 
	{zero seconds indicates no timeout} 
 
>   
	{look for string upon p command; if hit goto label} 
	{incoming linefeeds ignored} 
	{first come, first served} 
	{maximum of 32 active > demons allowed} 
 
?  
	{goto label if Clear To Send or Tx Hold Reg Empty is false} 
 
d  
	{goto label if Carrier Detect is true} 
 
<  
	{send string to port} 
 
!  
	{send string to console} 
 
x   
	{run executable file with arguments and wait for termination} 
	{goto label # if non-zero exit code} 
 
s   
	{run system command line and wait for termination} 
	{goto label # if error in running command.com} 
	{will not report errors within command string} 
 
+ 
	{Raise DTR handshake line} 
 
- 
	{Drop DTR handshake line} 
 
k   
	{set branch to label upon keyboard character received in w function} 
	{limit 64 simultaneous characters pending} 
 
w  
	{wait seconds for keyboard character, performing k dispatching} 
	{fall through if no character in  seconds} 
	{zero seconds indicates no timeout} 
	{clears all k commands pending upon any termination} 
 
c 
	{clears pending lookfors and keys (> and k)} 
 
q  
	{quit with exit code} 
	{codes other than zero under 128 are reserved to internals} 
 
When scripting modem commands, which is how you're intended to 
configure and dial the modem, try a ~ before and after the at, for 
instance: 
 
	< ~at~&f&c1&d2| 
 
The program SCRCHK types a listing of the argument script file giving 
statement numbers, which are not the same as line numbers. It leaves 
out blank lines for some reason. It also detects some errors, 
including potential branching to undefined labels. It prints out a 
table of label numbers with their corresponding line numbers. 
 
During execution of a script, Control-C will cancel and Control-X can 
redirect the script on an interrupt basis. 
 
All of the I/O programs except TERM pay attention to CTS. None of 
them do XON/XOFF. The computer is assumed to be fast enough to keep 
up. However, since DOS video is very slow, TERM will suspend display 
if a buffer overrun threatens. 
 
 
FAX PROGRAMS 
 
RCVFAX receives a fax from a Class 2 modem. It is intended to be 
called immediately after the "FAX" response. See HOSTDEMO.SCR for how 
to configure the faxmodem. RCVFAX uses the first speed until it sees 
the "+FCON" message, then switches to the second speed, which will 
generally be 19200 with Rockwell-based modems. It stimulates page 
transmits, and stores the session in the specified directory in a 
file of which the name is the universal time as an 8-digit hex number 
with the extension .RFX. 
 
Since the filenames are awkward, FAXMANIP, when run in the fax 
directory, displays RFX files as dates and times, and allows you to 
convert or delete. A secret FAXMANIP function is E, which will run a 
system call on the first argument, space, filename. This is intended 
for editing, by the adventurous. Also, when an argument is given to 
FAXMANIP, debugging output is turned on in RFXTOPCX. 
 
RFXTOPCX converts an RFX file to a series of PCX files, prompting for 
the name of each page file and reporting status. A second argument 
turns on debugging output.