Powershell threads logging to single output file? - multithreading

Question

Given a script the implements multi-threaded operations via a runspace pool, how does one get all the threads to output to a single file? I understand there are synchronization and/or locking issues to deal with, I'm just not sure what options are available.
Here is an example of how my threads are created. The example code hangs.
$_ps = [Powershell]::Create()
$_ps.RunspacePool = $_runspace_pool
$null = $_ps.AddScript({
Param (
[Parameter(Mandatory = $true)]
$ComputerName,
[Parameter(Mandatory = $true)]
$LibPath,
[Parameter(Mandatory=$false)]
$Logger = $null
)
$ErrorActionPreference = 'SilentlyContinue'
Import-Module -Name "$LibPath\MyObjectModule" -Force
$_obj = MyObjectModule\New-MyObject
if ( $Logger ) { $_obj.Logger = $Logger }
$_obj.InvokeDiscovery($ComputerName)
}) # end of $_ps.AddScript()
# set script parameters
$null = $_ps.AddParameters(#{ComputerName = $_computer; LibPath = $_lib_path; Logger = $_logger})
I'm thinking I might create a synchronized sorted list as a queue that is added to a logger object in my root thread and also passed to each child thread. Separate logger objects could be instantiated in each child thread that will put messages into the synchronized queue. The root thread logger would periodically flush the queue via a call like $logger.flush().
Maybe something like this...
$_queue = some synchronized queue-like object
$_logger = MyLoggerModule\New-MyLogger
$_logger.queue = $_queue
$_ps = [Powershell]::Create()
$_ps.RunspacePool = $_runspace_pool
$null = $_ps.AddScript({
Param (
[Parameter(Mandatory = $true)]
$Queue,
...
)
$ErrorActionPreference = 'SilentlyContinue'
Import-Module -Name "$LibPath\MyObjectModule" -Force
Import-Module -Name "$LibPath\MyLoggerModule" -Force
$_obj = MyObjectModule\New-MyObject
$_logger = MyLoggerModule\New-MyLogger
$_logger.queue = $Queue
$_obj.InvokeDiscovery($ComputerName)
}) # end of $_ps.AddScript()
# set script parameters
$null = $_ps.AddParameters(#{ComputerName = $_computer; LibPath = $_lib_path; Queue = $_queue})
# wait for threads to complete
do {
$_logger.flush()
Start-Sleep -seconds 5
} ( threads still running )
Assuming that made sense, is it a workable solution? Are there other options? Am I barking up an impossible tree and should abandon the idea altogether?

Answer 1

I was able to solve my problem by implementing creating a mutex and passing it to relevant functions. Worked like a charm.