xc.nro

支持X/YModem和cis_b+协议的串口通讯程序

    bind_function 26 "quitchr"

This binds Control-Z to quit the XC program.
.TP
.I bind_script
Syntax: bind_script \fIcode\fR "scriptname"

Bind the character identified by the number specified by \fIcode\fR to execute
the script named by "scriptname".

Upon termination of the script, the program will resume terminal mode, unless
the "quit" script function was executed.

Examples:

    bind_script 18 "/usr/lib/xc/.rz"

This binds Control-R to execute the script /usr/lib/xc/.rz. The .rz script
supplied with the source code contains:

    tty "on"
    echo -n "What files are to be received? "
    read FILES
    transmit "sz -y "
    transmit FILES
    transmit "^M"
    echo "Starting ZMODEM Receive (rz -y)"
    pipe "rz -y"

Pressing \fBXCAPE\fR \fB^R\fR will ask for some file name(s), and start an
.B sz
command on the remote system, and an
.B rz
on the local system to receive the file(s).

    bind_script 19 "/usr/lib/xc/.sz"

This binds Control-S to execute the script /usr/lib/xc/.sz. The .sz script
supplied with the source code contains:

    tty "on"
    echo -n "What files are to be sent? "
    read FILES
    echo "Starting ZMODEM send (sz -y " FILES ")"
    pipe "sz -y " FILES

Pressing \fBXCAPE\fR \fB^S\fR will ask for some file name(s), and then launch
.B sz
on the current system.
.B Sz
will itself start an
.B rz
process on the remote system.

.TP
.I bind_string
Syntax: bind_string \fIcode\fR "string"

Bind the character identified by the number specified by \fIcode\fR to emit the
string specified by "string".

The string is sent to the modem untranslated; eg, it is not examined for
embedded terminal mode escapes.

Example:

    bind_string 49 "AAATZ^M"

This binds "1" to send the sequence to reset the modem.
.TP
.I break
Syntax: break

Exits from the immediately enclosing 'while' loop. Identical to the C language
\&'break', and to the Bourne shell 'break' except that the
.B xc
script language 'break' does not take a numeric argument. Don't confuse this
with the script keyword 'xmitbrk', which sends a BREAK signal to the modem port.
.TP
.I call
Syntax: call "scriptname"

Suspends execution of the current script, and attempts to load and run the
specified scriptname. The scriptname must be a quoted literal string. There is
no
.B xc
analogue of the Bourne shell "exec" command; all subscripts in
.B xc
are treated as sub-routines. All variables are global across subscripts, so if
a subscript changes the value of a variable, then that change will remain in
effect after return to the parent script. Shell environment variables cannot be
changed by any
.B xc
script.
.TP
.I capture
Syntax: capture "on"
        capture "off"

Turns the file-capture function on or off. Note that the arguments must be
quoted literal strings. Note also that when the script exits into terminal
mode, the file-capture function is turned off. If you have 'set auto "on"',
then you will begin capturing immediately upon entering, or returning to,
terminal mode. If not, then you must manually type "\fBXCAPE\fR \fBY\fR" to
start capturing when entering terminal mode.
.TP
.I continue
Syntax: continue

Resumes execution at the top of the immediately enclosing 'while' loop.
Identical to the C language 'continue' instruction, and to the Bourne shell
\&'continue' command except that no numeric argument is accepted.
.TP
.I debug
Syntax: debug "on"
        debug "off"

If the 'debug' option is on, then
.B xc
will make many parenthetical comments about what it's doing while it runs the
script. These comments can sometimes be helpful in debugging script logic. Note
that the argument must be a quoted literal string.

While debugging a script containing a password, turn this option off, then on
again, to reduce the excitement-level of any colleagues collected circa your
screen.
.TP
.I decr
Syntax: decr <numeric-variable>

Decrements the value of the specified numeric user variable by 1. Useful in
controlling loop execution. If the specified variable isn't numeric, or doesn't
exist, a syntax error results.
.TP
.I dial
Syntax: dial "number-string"

Dials the specified number, using modem-command strings defined in xc.h.
The number should not contain spaces; dashes are acceptable.
.TP
.I echo
Syntax: echo "string" <variable> ...
        echo -n "string" <variable> ...

This command sends its arguments to the user's terminal. The number of
arguments is optional, except that the total result may not exceed 80
characters. Variables and back-quoted shell commands are expanded as necessary.

If the "-n" switch is present, then no carriage-return/newline sequence is
appended to the output.

Examples:

    echo "The time and date are now " `date`
    echo "My terminal type is " $TERM
    echo "My terminal type is " $TERM " today."

Note that whitespace isn't echoed unless it's part of a quoted literal string.
.TP
.I exit
Syntax: exit

Terminates execution of the current script. If a script reaches its end, it
exits automatically, so 'exit' is useful mainly to terminate a script
prematurely.
.TP
.I false
Syntax: false

Same as the Unix 'false' command. Does nothing, but returns a FALSE status
value. Useful within conditional expressions.

Example:

    if waitfor "CONNECT" 30 eq false
    then
        quit
    endif

Note that above example could be rewritten using the negating modifier "!":

    if ! waitfor "CONNECT" 30
    then
        quit
    endif

and note too that the "!" must be separated from its argument by whitespace.
.TP
.I file
Syntax: file <script-command>

The standard output of the specified script command is sent to the current
capture file. If the "capture" option is not set, then an error message is
displayed, but script execution continues.

Examples:

    file echo "--------- CUT HERE ----------"

Sends the output of the 'echo' command to the current capture file, provided
that the "capture" option is now "on".

    file echo `date`

Sends a timestamp to the current capture file, provided that the "capture"
option is now "on". The same thing could have been done with

   file shell "date"

.TP
.I hangup
Syntax: hangup

Tells the modem to go on-hook.

.TP
.I if\ \ 
Syntax: if <list1>; then <list2>; [ else <list3>; ] endif

If <list1> evaluates as TRUE, performs <list2>; otherwise, if <list3> is
specified, performs <list3>; then resumes execution immediately following
\&'endif'. To accommodate those whose minds wander while writing scripts, 'fi'
is an acceptable synonym for 'endif'.

Each list may consist of any number of script commands separated by semicolons
or newlines. The value of <list1> is determined by inclusively OR'ing the value
of each directive in the list, so that if any of the directives in <list1>
evaluates as TRUE, then so will <list1>. <list1> is performed in its entirety
regardless of the value of any of its component commands.

The keywords 'then', 'else', and 'endif' (or 'fi') must be immediately preceded
by command separators, either a semicolon or a newline, just as is the case in
the Bourne shell.

For conditional evaluation in 'if' and 'while' constructions, the following
comparators are available in addition to the script directives mentioned
elsewhere:

    <varname1> eq "string"
    <varname1> eq <number>
    <varname1> eq <varname2>
    <varname1>
    "string"

evaluates as TRUE if the value of user variable <varname1> is the same as that
of a specified string or numeric constant or of a specified second variable
name. If the variable name <varname1> is not followed by anything else, then
the expression evaluates as TRUE if the variable is numeric and has a non-zero
value, or if the variable is a string variable and has a non-zero length;
otherwise, the expression evaluates as FALSE. Comparing a string variable to a
numeric variable, or vice-versa, causes a syntax error.

If a conditional expression consists only of a quoted literal string, the
expression evaluates as TRUE if the string's length is non-zero, and otherwise
evaluates to FALSE. Because environment variables and back-quoted shell
commands are treated as if their output/value were quoted literal strings, this
allows direct testing of a shell command or of an environment for non-zero
length. Nonexistent environment variables are treated as if they exist with the
value "" (a string of zero length).

    <varname1> neq "string"
    <varname1> neq <number>
    <varname1> neq <varname2>

evaluates as TRUE if the value of user variable <varname1> is not equal to that
of a specified string or numeric constant or of a specified second variable
name. Comparing a string variable to a numeric variable, or vice-versa, causes
a syntax error.

    <varname1> lessthan "string"
    <varname1> lessthan <number>
    <varname1> lessthan <varname2>

evaluates as TRUE if the value of user variable <varname1> is less than that of
a specified string or numeric constant or of a specified second variable name.
String variables are compared lexically according to ASCII value.

    <varname1> morethan "string"
    <varname1> morethan <number>
    <varname1> morethan <varname2>

operates identically to 'lessthan', except in reverse.

The value of any conditional expression may be negated by preceding it with an
exclamation point followed by a space or tab.

Examples:

    if counter eq 0; then break; endif;
    if var1 eq var2; then echo "identical"; endif
    if counter morethan 20; then break; endif;
    if counter lessthan 0; then break; endif;
    if ! counter; then echo "counter is " counter; endif

To perform a list if any of a set of conditions exist:

    if counter morethan 5;
        counter eq brkvalue;    # a second comparator
    then break;
    endif;

i.e., perform the 'break' directive if the value of numeric user
variable 'counter' is greater than the numeric constant 5, or if the value
of 'counter' is equal to that of the user numeric variable 'brkvalue'.
.TP
.I incr
Syntax: incr <numeric-variable>

Increments the value of the specified numeric user variable by 1. The
opposite of 'decr'.
.TP
.I linked
Syntax: linked

\&'linked' is a pseudo-function that evaluates as TRUE if the current script has
been invoked from the dialing directory, and as FALSE otherwise.

Example:

    if ! linked; then
        dial "5551212"
    endif
.TP
.I pause
Syntax: pause <number>

Suspends execution for the specified <number> of SECONDS. Identical to Unix
"sleep."
.TP
.I pipe
Syntax: pipe "<shell-command>"

The standard input and standard output of the specified shell command are
connected to the modem port, and the command is executed. This is the
equivalent of the command mode "$" command.

Examples:

    pipe "echo \\"\\177\\""

sends a DELETE character to the modem.

    pipe "rz"

performs a file receive via ZMODEM, assuming that Chuck Forsberg's 'rz/sz'
programs reside on your system.

.TP
.I portname
Syntax: portname

This isn't a command, but a synonym for the current modem terminal device,
treated as if it were a quoted string. Useful if modems of differing types are
attached to different terminal lines and need different dialing or
initialization sequences. To compare the value of 'portname' to some other
string, you must first assign a user variable equal to 'portname'.

Examples:

    assign myport eq portname
    if myport eq "/dev/tty01"
    then
        transmit "AT&E0^M"
    endif
.TP
.I quit
Syntax: quit

Exits the script and terminates
.B xc
entirely. Any LCKfile will be removed if possible and the
user's terminal will be restored to the state it was in when
.B xc
was invoked.
.TP
.I read
Syntax: read <variable-name>

Takes a string from the user's keyboard and places it into the specified user
variable. Any previous value of the specified variable is discarded.
.TP
.I redial
Syntax: redial

Redials the number most recently dialed with the 'dial' command.
.TP
.I seen
Syntax: seen "string" <number>

Evaluates as TRUE if "string" has occurred within the last <number> characters
received during the most recent 'waitfor' command. Only up to 2048 characters
are remembered at any one time during 'waitfor' processing. If no <number> is
specified, then all the characters received during the most recent 'waitfor'
command are examined, up to a maximum of 2048. The 'seen' buffer is reset at
the beginning of each 'waitfor' command. This is useful to tell which of
several strings has been received.

Example:

    if waitfor "string1" 20
    then
        echo "Received 'string1'."
    else
        if seen "string2"
        then