linux - 如何在 expect shell 脚本中获取生成进程的退出代码？

Question

我正在尝试执行一个脚本，该脚本执行一个 EXPECT 脚本和一个包含退出代码的派生进程。但是我无法将衍生进程的退出代码获取到主脚本。我的成功总是零。

期望脚本是:

 [Linux Dev:anr ]$ cat testexit.sh
 #!/bin/bash
 export tmp_script_file="/home/anr/tmp_script_temp.sh"
 cp /home/anr/tmp_script $tmp_script_file
 chmod a+x $tmp_script_file
 cat $tmp_script_file
 expect << 'EOF'
 set timeout -1
 spawn  $env(tmp_script_file)
 expect {
 "INVALID "  { exit 4 }
 timeout     { exit 4 }
 }
 EOF
 echo "spawned process status" $?
 rm -f $tmp_script_file
 echo "done"

衍生脚本:

 [Linux Dev:anr ]$ cat tmp_script
 exit 3

Expect 脚本的执行:

 [Linux Dev:anr ]$ ./testexit.sh
 exit 3
 spawn /home/anr/tmp_script_temp.sh
 spawned process status 0
 done

问题是我无法获得生成的退出返回代码来期望脚本。我希望生成脚本的退出代码 3 到主脚本，并且主脚本应该以退出代码 3 退出。

请帮助我将生成的退出代码获取到主脚本。

Answer 1

您可以使用 wait 命令获取衍生进程的退出状态:

expect <<'END'
log_user 0
spawn sh -c {echo hello; exit 42}
expect eof
puts $expect_out(buffer)

lassign [wait] pid spawnid os_error_flag value

if {$os_error_flag == 0} {
    puts "exit status: $value"
} else {
    puts "errno: $value"
}
END

hello

exit status: 42

来自expect man page

wait [args]

delays until a spawned process (or the current process if none is named) terminates.

wait normally returns a list of four integers. The first integer is the pid of the process that was waited upon. The second integer is the corresponding spawn id. The third integer is -1 if an operating system error occurred, or 0 otherwise. If the third integer was 0, the fourth integer is the status returned by the spawned process. If the third integer was -1, the fourth integer is the value of errno set by the operating system. The global variable errorCode is also set.

---

改变

expect {
"INVALID "  { exit 4 }
timeout     { exit 4 }
}

到

expect {
    "INVALID "  { exit 4 }
    timeout     { exit 4 }
    eof
}

然后添加lassign 和if 命令。