Tcl期望：变量发送对复杂认证提示的响应

Question

这是摘自已知与Telnet服务器一起工作的TCL脚本的相关部分。

#!/bin/sh 
# \ 
exec tclsh "$0" ${1+"[email protected]"} 
package require Expect 
#USER 
set user xyz 
set secret 12345678 
set smr AB1CDE-11 
set host foo.bar 
#TELNET START 
spawn telnet $host 
expect "\[Login :\]" 
send "$user\r"; 
expect "=>" 
#RMS 
send "c $smr gate\r"; 
expect "$smr >" 
send "PW $secret\r" 
expect "\[>\]" 

几天前登录过程发生了变化。无法与send "PW $secret\r"联系。在$smr >响应之后，可发送任何命令以发起登录，例如， send "login\r"。 telnet回应Login [517]:。 []内的数字对应于$secret中的位置。完整的$secrect响应不再成功。服务器需要一个包含全部三个字符和三个附加字符的响应。

出于某些原因，我希望$secret中字符的位置处于三个随机字符（RegEx字词中的可能字符：[[email protected]#$%^&*()_]）之间的随机位置。 $secret的长度是可变的。所以我无法为每个角色设置一个变量来响应他们的RegEx匹配结果。

正确的RegExp捕获字符的位置将是LOGIN \[(\d)(\d)(\d)]:，对不对？我已经得到了以下内容（由于我正在评估登录过程的随机性，所以输出在统计后处理的文本文件中被捕获）。

send "login\r"  
set input [open output_$user.txt a] 
set output $expect_out(buffer) 
puts $input $output 
close $input 
expect "LOGIN" 
#Check LOGIN prompt 
set file [read [open "output_$user.txt" r]] 
if [ 
regexp -nocase {LOGIN \[(\d)(\d)(\d)]:} 
] then { 
send "RESPONSE\r"; 
} 

我该如何解决TCL的问题？谢谢！

Ammendment：
连接到Telnet服务器与send "c $smr gate\r";

XYZ SMC via AB1CDE-11 > 

被回答后，目前正由expect "$smr >"预期。在此之前，一切正常。
以下send "login\r"，Telnet服务器与两行回复：

Login [517]: 
XYZ SMC via AB1CDE-11 > 

匹配正则表达式将是Login \[(\d)(\d)(\d)\]:\n.*>。 我已经尝试了不同的期待正则表达式语法：
多纳尔共枕expect -re {Login \[(\d)(\d)(\d)\]:}崩溃TCL的
expect -re -n {Login \[(\d)(\d)(\d)\]:\n.*>} TCL的崩溃
expect {-re -n "Login \[(\d)(\d)(\d)\]:"}出口
只有一些不正规表达式（-re）像expect "$smr >"或expect "LOGIN"作品，以及TCL一点儿也不出口。
TCL程序兼容性（文件夹的路径已经被匿名）：

<?xml version="1.0" encoding="UTF-16"?> 
<DATABASE> 
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</EXE> 
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</EXE> 
<EXE NAME="kernel32.dll" FILTER="GRABMI_FILTER_THISFILEONLY"> 
    <MATCHING_FILE NAME="kernel32.dll" SIZE="1067008" CHECKSUM="0xD3859AE" BIN_FILE_VERSION="5.1.2600.6532" BIN_PRODUCT_VERSION="5.1.2600.6532" PRODUCT_VERSION="5.1.2600.6532" FILE_DESCRIPTION="Client-DLL für Windows NT-Basis-API" COMPANY_NAME="Microsoft Corporation" PRODUCT_NAME="Betriebssystem Microsoft® Windows®" FILE_VERSION="5.1.2600.6532 (xpsp_sp3_qfe.140312-0419)" ORIGINAL_FILENAME="kernel32" INTERNAL_NAME="kernel32" LEGAL_COPYRIGHT="© Microsoft Corporation. Alle Rechte vorbehalten." VERFILEDATEHI="0x0" VERFILEDATELO="0x0" VERFILEOS="0x40004" VERFILETYPE="0x2" MODULE_TYPE="WIN32" PE_CHECKSUM="0x10EBEB" LINKER_VERSION="0x50001" UPTO_BIN_FILE_VERSION="5.1.2600.6532" UPTO_BIN_PRODUCT_VERSION="5.1.2600.6532" LINK_DATE="03/12/2014 10:48:40" UPTO_LINK_DATE="03/12/2014 10:48:40" VER_LANGUAGE="Deutsch (Deutschland) [0x407]" /> 
</EXE> 
</DATABASE> 

是的，我使用的是Windows这一点。由于this issue，无法使用Linux进行此任务。
我应该怎么做？

Answer 1

那么，通过使用Expect的更多功能，您可以很容易地完成一些操作。特别是，expect命令可以等待正则表达式匹配并报告哪些子字符串匹配，然后使用string index从字符中挑选字符。

expect -re {Login \[(\d)(\d)(\d)\]:} 
# It's wise to copy these values from expect_out into other variables immediately 
set digitA $expect_out(1,string) 
set digitB $expect_out(2,string) 
set digitC $expect_out(3,string) 

# Is it zero-based or one-based indexing? Assuming the latter... 
set charA [string index $secret [expr {$digitA - 1}]] 
set charB [string index $secret [expr {$digitB - 1}]] 
set charC [string index $secret [expr {$digitC - 1}]] 

我不太清楚你如何组装这些文字转化成反应 - 你的描述不够清楚 - 但我相信你能明白这一点，现在你已经得到了原料。