自动telnet会话获取天气：
thufir@dur:~/NetBeansProjects/spawnTelnet/telnet$
thufir@dur:~/NetBeansProjects/spawnTelnet/telnet$ tclsh main.tcl
connect to wunderground with:
-----------------
1) noControlFlow
2) connect
1
spawn telnet rainmaker.wunderground.com
getting weather for nyc
Trying 35.160.169.47...
Connected to rainmaker.wunderground.com.
Escape character is '^]'.
------------------------------------------------------------------------------
* Welcome to THE WEATHER UNDERGROUND telnet service! *
------------------------------------------------------------------------------
* *
* National Weather Service information provided by Alden Electronics, Inc. *
* and updated each minute as reports come in over our data feed. *
* *
* **Note: If you cannot get past this opening screen, you must use a *
* different version of the "telnet" program--some of the ones for IBM *
* compatible PC's have a bug that prevents proper connection. *
* *
* comments: jmasters@wunderground.com *
------------------------------------------------------------------------------
Press Return to continue:
Press Return for menu
or enter 3 letter forecast city code-- nyc
Weather Conditions at 03:51 AM EDT on 10 May 2020 for New York JFK, NY.
Temp(F) Humidity(%) Wind(mph) Pressure(in) Weather
========================================================================
40 55% WEST at 20 30.08 Partly Cloudy
Forecast for New York, NY
319 am EDT sun may 10 2020
.Today...Sunny. Highs in the lower 60s. West winds 15 to 20 mph.
.Tonight...Mostly cloudy. A chance of showers after midnight.
Lows in the upper 40s. Southwest winds 15 to 20 mph, diminishing
to 5 to 10 mph after midnight. Chance of rain 30 percent.
.Monday...Mostly cloudy with a chance of showers. A slight chance
of thunderstorms in the afternoon. Highs in the lower 60s. West
winds 10 to 15 mph. Chance of rain 50 percent.
.Monday night...Mostly cloudy with a slight chance of showers in
the evening, then mostly clear after midnight. Lows in the lower
40s. Northwest winds 15 to 20 mph. Chance of rain 20 percent.
.Tuesday...Sunny. Highs in the upper 50s. Northwest winds 10 to
15 mph.
.Tuesday night...Partly cloudy. Lows in the lower 40s.
.Wednesday...Sunny. Highs in the lower 60s.
.Wednesday night...Mostly clear in the evening, then becoming
Press Return to continue, M to return to menu, X to exit: thufir@dur:~/NetBeansProjects/spawnTelnet/telnet$
thufir@dur:~/NetBeansProjects/spawnTelnet/telnet$
代码：
package provide weather 1.0
package require Expect
namespace eval ::wunderground {
}
#works
proc ::wunderground::noControlFlow {city} {
variable telnet [spawn telnet rainmaker.wunderground.com]
puts "getting weather for $city"
expect "Press Return to continue:"
send "r"
expect "or enter 3 letter forecast city code--"
send "$cityr"
expect "X to exit"
send "x"
}
如何在上面的脚本中添加一些逻辑或控制流？
例如，从proc本身打印几个硬编码的城市，并提供一个菜单从中进行数字选择？
类似main脚本的东西：
lappend auto_path /home/thufir/NetBeansProjects/spawnTelnet/telnet/weather
package require weather 1.0
puts "nnconnect to wunderground with:"
puts "-----------------"
puts "1)tnoControlFlow"
puts "2)tconnectnn"
set a [gets stdin]
if {$a == 1 } {
wunderground::noControlFlow "nyc"
} else {
wunderground::connect "nyc"
}
是的，显然神童乐园提供了一份城市菜单供选择。只是想增加一些分支来启迪。
我相信，在expect语句上切换-i，以进入和退出交互模式。
我已经将期待的man页面发送到我的kindle，并考虑在期待时购买这本书
您可以使用普通的Tcl控制流结构，如带有Expect命令的if和foreach。(您已经使用proc完成了其中的一些操作。(唯一真正棘手的一点(尤其是循环和Expect(是，您需要思考您正在做什么，以及正在进行的自动化操作。
你最终得到的可能看起来像这样。
proc ::wunderground::multipleCities {args} {
variable telnet [spawn telnet rainmaker.wunderground.com]
puts "getting weather for $city"
expect "Press Return to continue:"
send "r"
foreach city $args {
expect "or enter 3 letter forecast city code--"
send "$cityr"
}
expect "X to exit"
send "x"
}
不过，我认为您可能应该以某种方式将循环中的expect结构在send之后，这样您就可以在概念上处理获取特定城市值的结果。您可能需要确定一个常见的稳定提示，以便在获取数据后返回。