关于多线程：在Powershell中等待C#事件时阻塞会导致死锁

Blocking While Waiting For C# Event In Powershell Causes Deadlock

在PowerShell中，我试图启动一个进程，然后等待直到该进程退出或脚本从命名管道中获取信号。虽然命名管道组件可以正常工作，但是当脚本被阻止时，代码无法处理事件。这只是事件相关代码的示例：

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$ErrorActionPreference ="Stop"

# launch process with the appropriate args.
$p = [System.Diagnostics.Process]::new()
$p.StartInfo.FileName ="notepad.exe"
$p.StartInfo.Arguments = $null
$p.EnableRaisingEvents = $true $p.Start()

# create a task completion source
$tcs = [System.Threading.Tasks.TaskCompletionSource[Boolean]]::new()

Register-ObjectEvent -InputObject $p -EventName Exited `
-MessageData $tcs `
-Action {
$Event.MessageData.SetResult($true)
}

# wait for the program to exit
$processTask = $tcs.Task

# this deadlocks
$processTask.Wait()

是否存在通过PowerShell的作业系统解决该问题的正确方法，还是通过手动旋转另一个等待该过程退出的C#任务来解决该问题，从而使脚本能够在发生任何一个事件后恢复运行？

作为参考，这是更完整的脚本(包括对流程事件或命名管道的等待)：

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$ErrorActionPreference ="Stop"

#inbound pipe
$pipeListener = [System.IO.Pipes.NamedPipeServerStream]::new("testPipe", 1)

# launch process with the appropriate args.
$p = [System.Diagnostics.Process]::new()
$p.StartInfo.FileName ="notepad.exe"
$p.StartInfo.Arguments = $null
$p.EnableRaisingEvents = $true
$p.Start()

# I would normally solve this using a TaskCompletionSource
# in C#, and have it fire off the process's exited event.

# create a task completion source
$tcs = [System.Threading.Tasks.TaskCompletionSource[Boolean]]::new()

Register-ObjectEvent -InputObject $p -EventName Exited `
-MessageData $tcs `
-Action {
$Event.MessageData.SetResult($true)
}

# wait for the program to exit, or for pipe signal
try {
$pipeTask = $pipeListener.WaitForConnectionAsync()
$processTask = $tcs.Task

while ($true)
{
echo"Launched Process, waiting for sequence to complete..."

# this works, but not instantly - the timeout appears to allow the
# event to process.
#$res = [System.Threading.Tasks.Task]::WaitAny(@($processTask, $pipeTask), 10000)

# this does not.
$res = [System.Threading.Tasks.Task]::WaitAny(@($processTask, $pipeTask))

echo"Got wait result: $res"

if ($pipeTask.IsCompleted) {
echo"Got pipe connection"
$sr = [System.IO.StreamReader]::new($pipeListener)
$msg = $sr.ReadToEnd()

echo"Pipe sent: $msg"
break
}

if ($processTask.IsCompleted) {
echo"Process completed."
break
}
}
}
finally {
$pipeListener.Dispose()
}