xc.nro

支持X/YModem和cis_b+协议的串口通讯程序

respectively set the modem port to a character size of 8 with no parity, or a
character size of 7 with either even or odd parity. During B-Plus or XMODEM
transfers, the port protocol is set to 8N, and reverts to its prior setting
thereafter.
T}

set xcape \fIchar\fR
set escape \fIchar\fR@T{
Set the \fBXCAPE\fR character (see below) to \fIchar\fR. This should be set to
some non-printing character (other than backspace, tab, newline, of course).
The character may be entered by depressing the Control key first
and then typing a letter, or by typing a carat (^) followed by a letter.
T}

set xon on|off
set xoff on|off@T{
Set XON/XOFF flow control flag. If "on", the program will honor the XOFF
control character and wait until an XON character is received before
transmitting any more information. If "off", the program will ignore
XOFF/XON requests. You probably want this set 'off' if you have rts/cts
flow control enabled. See next entry.
T}

set rtscts on|off@T{
Enable your comm port to use hardware flow control. If you select this
option, you must also tell your modem to use rts/cts too. See your 
modem manual for details. Generally, this is the preferred method of
flow control.
T}

set del2bs on|off@T{
Because the Linux backspace key does not actually send the backspace
character but '\177' (delete character) instead, XC can trap it and
translate it to its proper value if you issue the command "set del2bs
on".  If you issue the command "set del2bs off", the backspace key
will echo '\177' the DEL character.  Normally this is only of interest
when connecting to a VAX machine which usually prefers the delete
character. Most public dial-in services and BBS prefer the backspace
charcter (^H). Enable this by 'set del2bs on'.
T}

set msdos on|off@T{
Sets translation of ASCII characters from the MS-DOS screen codes to
LINUX screen codes. Set this mode "on" when connected to DOS BBSs.
Note that LINUX does not support all the special characters and
symbols available under MS-DOS. Where no exact match is avail- able,
the best possible substitution is made. Note that under LINUX that
special characters can be typed by holding down the <alt> key and
typing another regular key. For example, typing <alt> <i> on a US
keyboard will produce an accented e', <alt> <I> will produced an
accented E'.
T}

set autozm on|off@T{
This option enables or disables the automatic reception
of files via the ZMODEM protocol. You must also set the
proper command string using the 'zmcmd' option below.
T}

set zmcmd command@T{
Use this option to specify the command line used 
when xc automatically invokes your external ZMODEM
receive protocol, for example 
"set zmcmd rz -v".
T}
.TE
.SS \fITerminal Mode\fR
In terminal mode, all characters typed at the keyboard are sent to the
modem, except that newline characters (0x0A) are translated to
carriage-returns (0x0D) when you have "set nl 'on'"; all characters received
from the modem are displayed on the local terminal screen.

\fBXCAPE\fR is a key that will, when typed in terminal mode, introduce an
.B xc
"escape" command. Don't confuse \fBXCAPE\fR with the <ESCAPE> key.
The default definition for \fBXCAPE\fR is ASCII 1, or Control-A. It can 
be redefined at run time with the "set escape \fIC\fR" command (or it can be
redefined in the
.I .xc
startup script).

When the \fBXCAPE\fR key is typed in terminal mode, the program will examine
the next key pressed. If this key has been "bound" to perform a certain
function, that function will be performed; otherwise, the second character is
sent to the modem. Thus, to send the \fBXCAPE\fR character through the modem,
it is necessary to press the key TWICE.

Thus the ESCAPE key itself would be a terrible choice for \fBXCAPE\fR, because
it is used so often by other programs: if you were logged into a remote system
and running, say, \fBvi\fR, it would be a great annoyance to have to hit ESCAPE
twice to get it transmitted once.

The following keys (case \fIin\fRsensitive) are bound at startup time. Others
may be added through the binding commands available in 
.B xc
scripts.

.TS
tab(@) ;
l2 l2 l
l2B l2 l .
Command@Function@Description

XCAPE /@Help@Display the table of bound keys
XCAPE ?@Help@Display the table of bound keys

XCAPE b@\fIB\fRREAK@Send a MODEM BREAK signal (a sustained null).

XCAPE d@\fID\fRirectory@Display the phone directory.

XCAPE f@\fIF\fRile@Send a file through the modem (ASCII transfer).

XCAPE s@\fIS\fRcript@\fBXc\fR will request the name of a script to execute.

XCAPE h@\fIH\fRangup@Tell the modem to go on-hook.

XCAPE o\fR@Graphics \fIO\fRff@T{
Clear vt102 graphics mode.
If line noise or some other phenomenon puts you in graphics mode
(weird characters being displayed instead of plain text), use this
command to toggle back to normal text mode. Note that previously
diplayed text is unaffected. Only subsequent text will be affected.
T}

XCAPE y\fR@Capture \fIY\fRes@T{
Open the capture file in APPEND mode (text received over the port accumulates
at the end of the file). If the file is already open, a message is printed to
that effect.
T}

XCAPE n\fR@Capture \fIN\fRo@T{
Close the capture file. If it wasn't open, a message of regret is printed.
T}

XCAPE x\fR@e\fIX\fRit@Exit terminal mode back to \fI<XC>\fR command mode.

XCAPE q@\fIQ\fRuit@Quit \fBxc\fR altogether.
.TE
.SS \fIPhonelist\fR
.B Xc
looks for a
.I phonelist
file in the following order: in the current directory, in your home directory
as defined by the $HOME environment variable, or in the LIBDIR as defined
at compile time in
.I xc.h.
However in command mode, any filename can be substituted, using the SET PFILE
command, so long as it has the following characteristics:

It is ASCII text (lines of text separated by newlines).

The first field of data in each line (after any whitespace and up to the next
occurence of whitespace) is a phone number in a valid format for
the modem being used.

Descriptive text may follow the phone number. Spaces may be included in this
text, but a <TAB> must terminate this text.

The following three definitions may then follow in any order:
.TP 12
PROTO=sss
(sss=7e2|7o2|8n1) Set the serial port protocol for 7-bit characters with
either even or odd parity and two stop bits, or for 8-bit characters with
no parity and one stop bit.
.TP
BPS=nnnn
(n=300|1200|2400|9600|19200|38400) Set the bits/second rate to the
specified value.
.TP
SCRIPT=file
Immediately after sending the autodial string, execute the script file
specified. (Note that the specified filename is CASE SENSITIVE!)
.P
The following definition, if used, must be the LAST field on the line.

PREFIX=xxxxxxxx (e.g., PREFIX=ATs110=0s111=0)

The PREFIX="string" allows you send your modem a different setup string for
each situation (default: no special setup). This is helpful for MNP and Telebit
modems which require special attention for contacting non-MNP modems and other
Telebits.
.SS \fIScripts\fR
The
.B xc
script language is intended to be closely similar to the Unix Bourne shell
language. Unfortunately, it isn't identical to the Bourne shell, so it has
the same problem that the
.BR awk (C)
program does for those experienced in the C language: an
.B awk
script LOOKS like C, but it isn't, really; and in the same way, an
.B xc
script LOOKS like a Bourne shell script, but isn't. So the operation of the
Bourne shell, if you're familiar with it, is useful as an analogy in
understanding the
.B xc
script language, but only as an analogy.

An
.B xc
script consists of lists of commands. Commands are set off from each other
within a list by either a newline ('\\n') or a semicolon (;), as is the case
with the Bourne shell. The semicolon and the newline have identical effect as
command separators, so (anticipating a bit here) you could say either

.nf
    if counter morethan 5
    then
       transmit "bye^M"
       quit
    endif

or

    if counter morethan 5; then transmit "bye^M"; quit; endif

.fi
and the result will be the same either way. The newline and the semicolon
are treated the same way as in the Bourne shell, except that a newline cannot
be quoted so as to remove its interpretation as a command terminator (in
other words, a quoted string cannot contain a newline).

Commands are composed of
.IR word s
separated by spaces or tab characters, and a
.I word
can be one of the following:
.TP 3
*
One of the
.B xc
script language keywords, which are listed below, with appropriate explanations.
.TP
*
A number, meaning a sequence consisting only of digits, with
an optional leading minus sign to indicate a negative number.
.TP
*
A literal string of characters surrounded by double-quotation marks ('"'); such
a string can be no longer than 80 characters. A double-quotation mark can be
imbedded within the string by preceding it with a backslash ('\\"'); when the
string is interpreted, the backslash is disregarded and the double-quotation
mark is treated as part of the string. Mismatched quotation marks result in a
syntax error.
.TP
*
The name of a user variable, which can have either a string or a numeric value.
The name of a user variable must begin with an alphabetic character.
.TP
*
The name of a shell environment variable, preceded by a dollar sign ('$'). The
.B xc
script language examines the Unix environment for the specified variable and,
if such a variable exists, substitutes the value of that variable. The result
is treated as if it were a quoted literal string, and, therefore, should not be
more than 80 charac\%ters long, or else it will be truncated to its first 80
characters. Similarly, such an environment variable should not contain a
newline.
.TP
*
An expression surrounded by back-quotation marks ('`'). This sort of expression
operates similarly to the Bourne shell's command-substi\%tution mechanism: the
contents of the back-quotes are passed to the Bourne shell, and the standard
output of the back-quoted command is treated as if it were a quoted literal
string. Therefore, the command's output should not be more than 80 characters
long, nor contain a newline. Also, the contents of the back-quotes cannot be
longer than 80 characters, nor contain a newline.
.TP
*
An expression introduced by a pound-sign (or number-sign: '#'), which is
treated as a comment. All characters from the '#' until the end of the
physical line are ignored. This comment mechanism is the same as in the
Bourne shell.
.TP
*
A limitation of the script language is that only one character string can be
passed as an argument to any of the script commands. The \fIbind_function\fR,
\fIbind_script\fR, and \fIbind_string\fR commands thus need to use a decimal
digit to represent the key that is to be bound. The ASCII value of the the key
is employed. As an example, Control-C is identified as 3, Control-Z is 26, the
ESCAPE key is 27, a space is 32, the number "1" is 49; letters are
.RI case- in sensitive
so that identifying the bound key as "65" or as "97" will always bind 
.I both 
"a" and "A" to the same command.
.P
Quoted literal strings (and the two other mechanisms that act like quoted
literal strings, shell environment variables and back-quoted shell commands)
may be up to 80 characters long. All other words must be no longer than 16
characters, and are treated case-independently (which is to say, uppercase
is the same as lowercase); note, though, that the names of shell environment
variables are case-dependent (uppercase must match uppercase and lowercase
must match lowercase), because they are case-dependent in the shell.

Any word not recognizable within the foregoing categories is treated as the
name of a new user variable. Such a word, if longer than 16 characters, is
considered to be a syntax error.

User variables are created with the 'assign' script keyword, and may have
either numeric or string values. The type of a user variable is determined
by how it's created; if it's assigned to a string, it's a string variable,
and if it's assigned to a number, it's a numeric variable. The value of any
user variable can be changed with another 'assign' command, and numeric
variables can be changed to string variables and vice-versa. Shell
environment variables cannot be changed within an
.B xc
script, but the value of a shell environment variable can be assigned to a user
variable, and the value of the user variable can thereafter be changed.

Scripts are contained in ASCII text disk files, one script to a file. A
script can invoke another script as a subroutine with the 'call' keyword; up
to 5 scripts can be nested in this way at any single time.

With all this said, the following list of
.B xc
script language commands should be comprehensible. The format "<something>"
means that a token, or word-type, of the "something" type is meant rather than
the literal sequence 'something'.
.SS \fIScript Language Commands\fR
Note that all the commands are case-\fIin\fRsensitive!
.TP 4
.I affirm
Syntax: affirm

Reads a string from the terminal, and returns TRUE if the string begins with
\&'y' or 'Y'; otherwise, returns FALSE.  Used in evaluating conditional
expressions. The string must be terminated by a newline or carriage-return.

Example:

    echo -n "Continue (y/n)? "
    if affirm
    then
        continue
    else
        break
    endif
.TP
.I assign
Syntax: assign <varname> eq <number>
        assign <varname> eq "string"
        assign <varname1> eq <varname2>
        assign <varname> eq <script-command>

Assigns to user variable <varname> the value following "eq"; if that value is a
number, then <varname> becomes a numeric user variable; if that value is a
string, then <varname> becomes a string user variable. If <varname> does not
already exist as a user variable, it is created. Variable space is allocated
dynamically, but running out of memory space for variables is unlikely. All
variables are global across scripts that run at the same time via the 'call'
keyword, and all variables vanish when a script, called directly from
.B xc
as opposed to called from another script, exits. In other words, variable
values are not static except during 'call' execution. Variable names cannot be
longer than 8 characters. Successive 'assigns' are permissible, and the type of
the variable changes according to the type of the value following "eq". A user
variable is destroyed with the 'unassign' keyword.

If a variable is assigned the value of a script command, then it becomes a
numeric variable with value TRUE or FALSE, depending on the status returned by
the script command. If a variable is assigned the value of a back-quoted
command, it becomes a string variable with the value of the first 80 characters
of the back-quoted command. If a variable is assigned equal to an environment
variable, it becomes a string variable with the value of the first 80
characters of the value of the environment variable.

Examples:

    assign numvar eq 5
    assign strvar eq "This variable is a string"
    assign mydir eq $HOME
    assign numvar2 eq numvar
    assign strvar2 eq strvar
    assign numvar eq true
    assign today eq `date`; echo "today is " today
.TP
.I beep
Syntax: beep

Sends a Control-G to the terminal. Useful for alerting the user that some event
has occurred, for example a CONNECT after a lengthy redialing session.
.TP
.I bind_function
Syntax: bind_function \fIcode\fR "function"

Bind the character identified by the number specified by \fIcode\fR to the
\fBxc\fR builtin function "function".

The "function" may be one of the following (case is ignored):

    BRKCHAR  Send modem BREAK signal
    CAPTEND  Turn off terminal mode capture
    CAPTYES  Turn on terminal mode capture
    DIALCHR  Dial from phonelist
    DIVCHAR  Send file through modem
    DOSCRPT  Execute script file (prompts interactively)
    EMITSTR  Emit string
    ENDCHAR  Exit terminal mode
    HLPCHAR  Display terminal mode key bindings
    HUPCHAR  Hang up modem
    QUITCHR  Quit program
    SCRPCHR  Prompt for script file

Example: