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TCL 预计不写入输出缓冲区

tag-icon • tag-icon linux expect tcl
TCL 预计不写入输出缓冲区

我注意到我的 TCL/Expect 脚本没有写入输出缓冲区。

`#!/usr/bin/expect -f

exp_internal 1; #Debug Expect

set username [lindex $argv 0]; #Takes Outside Argument
set password [lindex $argv 1]; #Takes Outside Argument
set hostFile [open hosts.txt r]; #Reads from a local file


while { [gets $hostFile hostname] >= 0 } {
spawn ssh -q -o StrictHostKeyChecking=no $username@$hostname
expect "password: "

send  "$password\r"
expect "$ "

send "pbrun /bin/su -"
expect {
 "Operations Team.*" {
  puts "NewLine Was Caught After pbrun /bin/su - command"
  #break #Exit While loop, which will exit the server since there is only one While Loop aprund the whole SSH Session
 }
 "Rejected.*" {
  puts "NewLine & Return Carraige Was Caught After pbrun /bin/su - command"
  #break #Exit While loop, which will exit the server since there is only one While Loop aprund the whole SSH Session
 }
 #"^" { ;#This command will work because in the expect only picks up a    "^" character from the [send "pbrun /bin/su -"] command. This is an issues as the pbrun command has more ouput that just a "^", but expect only picks up the "^" character. You can use any other command like "ls", and expect does not write the ls command ouput to the buffer, only a newline character will be written to the buffer. This is an issue as I am unable to grab anything from expect.
 # puts "Newline Character Met"
 #}
}

send "hostname\r"
expect {
 -re {".{8}[0-9]{5}"} {; #Never Works
  puts "BUFFER:$expect_out(buffer):REFFUB"
 }
 "^" {; #Again, this will be met
  puts "Newline Character Met"
 }
}
}`

任何帮助深表感谢。我在调试模式下运行它，确实看到除了字符之外，没有任何输出被写入pbrun /bin/su -or命令的缓冲区。hostname^

答案1

您的实际问题：该模式{".{8}[0-9]{5}"}将匹配包含双引号、后跟 8 个字符、后跟 5 个数字、后跟双引号的字符串 - 这些双引号是否应该出现在您的模式中？有时人们会对 Tcl 的引用感到困惑，所以我的问题并不意味着带有任何判断。

另外，当您在 Expect 块中有 2 个模式时，任何一个都可以第一个匹配：您是否期望看到 8 个字符和 5 个数字前第一个换行符？

等等，^将在第一行的开头匹配。如果您想显式匹配换行符，请使用\n.

不幸的是，Tcl 的注释处理可能会令人困惑。评论字符# 仅有的开始评论如果看到命令可以去的地方。

您在期望块中放入的注释不要注释掉这些行。

expect {
 "Operations Team.*" {
  puts "NewLine Was Caught After pbrun /bin/su - command"
  #break #Exit While loop, which will exit the server since there is only one While Loop aprund the whole SSH Session
 }
 "Rejected.*" {
  puts "NewLine & Return Carraige Was Caught After pbrun /bin/su - command"
  #break #Exit While loop, which will exit the server since there is only one While Loop aprund the whole SSH Session
 }
 #"^" { ;#This command will work because in the expect only picks up a    "^" character from the [send "pbrun /bin/su -"] command. This is an issues as the pbrun command has more ouput that just a "^", but expect only picks up the "^" character. You can use any other command like "ls", and expect does not write the ls command ouput to the buffer, only a newline character will be written to the buffer. This is an issue as I am unable to grab anything from expect.
 # puts "Newline Character Met"
 #}
}

您实质上是向命令传递一个包含和对的expect列表。第三个模式实际上是 4 个字符，第三个操作是一个包含脚本的字符串，该脚本包含 3 个注释。patternaction#"^"

答案2

默认情况下，pbrun 在终端会话中运行。我不是TCL专家，但是通过shell脚本运行pbrun时，pbrun在处理pbun的输出时有时需要以管道模式运行。

"pbrun -p <command> | /usr/local/bin/db_check.sh"

此外，在处理发送 pbrun 命令时，您可能还想使用 -n （空输入），并且没有通过 stdin 的输入，但由于调用 pbrun 的脚本不干净，所以 pbrun 会以某种方式获取一些缓冲数据。

   -n,  --null_input
          Redirects  the  standard input of pbrun to /dev/null.  You some‐
          times need this option to avoid interactions between  pbrun  and
          the  shell  that  invokes  it.   For example, if you are running
          pbrun and start a pbrun in the  background  without  redirecting
          its input away from the terminal, it will block even if no reads
          are posted by the remote command.   This  option  corrects  this
          situation.


   -p,  --pipe_mode
          Pipe mode. Forces the secured task to behave as if it is run  in
          a  pipeline  rather  than  a terminal session.  This option also
          suppresses utmp  entries,  so  that  the  session  will  not  be
          recorded as a login on the runhost.

最后一项，“Rejected”消息返回到 stderr，而不是 stdout。

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