27

I want to capture stdout and stderr from a process that I start in a Powershell script and display it asynchronously to the console. I've found some documentation on doing this through MSDN and other blogs.

After creating and running the example below, I can't seem to get any output to be displayed asynchronously. All of the output is only displayed when the process terminates.

$ps = new-object System.Diagnostics.Process
$ps.StartInfo.Filename = "cmd.exe"
$ps.StartInfo.UseShellExecute = $false
$ps.StartInfo.RedirectStandardOutput = $true
$ps.StartInfo.Arguments = "/c echo `"hi`" `& timeout 5"

$action = { Write-Host $EventArgs.Data  }
Register-ObjectEvent -InputObject $ps -EventName OutputDataReceived -Action $action | Out-Null

$ps.start() | Out-Null
$ps.BeginOutputReadLine()
$ps.WaitForExit()

In this example, I was expecting to see the output of "hi" on the commandline before the end of program execution because the OutputDataReceived event should have been triggered.

I've tried this using other executables - java.exe, git.exe, etc. All of them have the same effect, so I'm left to think that there is something simple that I'm not understanding or have missed. What else needs to be done to read stdout asynchronously?

Ci3
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  • How about start-process? `start-process -nonewwindow cmd '/c timeout 5 & echo hi'` – js2010 Nov 02 '19 at 14:20
  • A note for others: A few of the various solutions below worked for me, but the process output was not streamed asynchronously; rather, it was printed all at once after the process had finished. The solution was to not use `$process.WaitForExit()`. I had to replace this line with an `while ( -Not $process.HasExited ) { sleep 1 }` to get the same effect while enabling streaming. – Blaisem Oct 11 '22 at 15:20

7 Answers7

46

Unfortunately asynchronous reading is not that easy if you want to do it properly. If you call WaitForExit() without timeout you could use something like this function I wrote (based on C# code):

function Invoke-Executable {
    # Runs the specified executable and captures its exit code, stdout
    # and stderr.
    # Returns: custom object.
    param(
        [Parameter(Mandatory=$true)]
        [ValidateNotNullOrEmpty()]
        [String]$sExeFile,
        [Parameter(Mandatory=$false)]
        [String[]]$cArgs,
        [Parameter(Mandatory=$false)]
        [String]$sVerb
    )

    # Setting process invocation parameters.
    $oPsi = New-Object -TypeName System.Diagnostics.ProcessStartInfo
    $oPsi.CreateNoWindow = $true
    $oPsi.UseShellExecute = $false
    $oPsi.RedirectStandardOutput = $true
    $oPsi.RedirectStandardError = $true
    $oPsi.FileName = $sExeFile
    if (! [String]::IsNullOrEmpty($cArgs)) {
        $oPsi.Arguments = $cArgs
    }
    if (! [String]::IsNullOrEmpty($sVerb)) {
        $oPsi.Verb = $sVerb
    }

    # Creating process object.
    $oProcess = New-Object -TypeName System.Diagnostics.Process
    $oProcess.StartInfo = $oPsi

    # Creating string builders to store stdout and stderr.
    $oStdOutBuilder = New-Object -TypeName System.Text.StringBuilder
    $oStdErrBuilder = New-Object -TypeName System.Text.StringBuilder

    # Adding event handers for stdout and stderr.
    $sScripBlock = {
        if (! [String]::IsNullOrEmpty($EventArgs.Data)) {
            $Event.MessageData.AppendLine($EventArgs.Data)
        }
    }
    $oStdOutEvent = Register-ObjectEvent -InputObject $oProcess `
        -Action $sScripBlock -EventName 'OutputDataReceived' `
        -MessageData $oStdOutBuilder
    $oStdErrEvent = Register-ObjectEvent -InputObject $oProcess `
        -Action $sScripBlock -EventName 'ErrorDataReceived' `
        -MessageData $oStdErrBuilder

    # Starting process.
    [Void]$oProcess.Start()
    $oProcess.BeginOutputReadLine()
    $oProcess.BeginErrorReadLine()
    [Void]$oProcess.WaitForExit()

    # Unregistering events to retrieve process output.
    Unregister-Event -SourceIdentifier $oStdOutEvent.Name
    Unregister-Event -SourceIdentifier $oStdErrEvent.Name

    $oResult = New-Object -TypeName PSObject -Property ([Ordered]@{
        "ExeFile"  = $sExeFile;
        "Args"     = $cArgs -join " ";
        "ExitCode" = $oProcess.ExitCode;
        "StdOut"   = $oStdOutBuilder.ToString().Trim();
        "StdErr"   = $oStdErrBuilder.ToString().Trim()
    })

    return $oResult
}

It captures stdout, stderr and exit code. Example usage:

$oResult = Invoke-Executable -sExeFile 'ping.exe' -cArgs @('8.8.8.8', '-a')
$oResult | Format-List -Force 

For more info and alternative implementations (in C#) read this blog post via archive.org or archive.is.

Vopel
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Alexander Obersht
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    Unfortunately, I don't get any stdout or stderr after running this code. – Ci3 Jun 23 '14 at 17:33
  • @ChrisHarris Re-tested (in PS 2.0) and it does work for me. Do you get any exception? Do you get any output when you run the same command directly? – Alexander Obersht Jun 23 '14 at 17:37
  • I get the object returned with null values for StdOut, StdErr. The exit code is "0". I was expecting the output of ping.exe with a reply, the bytes, time, etc. Is that right? I ran it exactly as you have it here. I'm running Powershell 4. Ah, just ran it on Powershell 2, and it works as expected! – Ci3 Jun 23 '14 at 17:39
  • Edited my answer - added code to remove and unregister events. Should work with PS3.0/PS4.0 now. – Alexander Obersht Jun 23 '14 at 20:25
  • I still have problems getting output only after execution of the process finishes. What I was able to do was to replace the WaitForExit() call, and instead use a while loop which works, but is not as elegant. However, this is exactly what I needed. Thanks for the help! – Ci3 Jun 23 '14 at 22:37
  • This worked fine for me in PS4. You do have to unregister the events before reading from the StringBuilder objects. – Todd Sep 22 '15 at 14:11
  • I've created another answer, based on yours, but using tasks instead of event handlers as more safer way according to http://www.codeducky.org/process-handling-net/ – Michael Freidgeim Apr 11 '16 at 03:16
  • You saved my day! – karliwson Apr 08 '18 at 21:15
  • I have an app that produces large output. I've tried many solutions, including yours and the one below, but I keep getting same problem: when I run the command directly, everything works properly; when I launch several commands in parallel as jobs, all processes hang. Any idea, what may be wrong? – Michał Sacharewicz Oct 24 '18 at 16:39
14

Based on Alexander Obersht's answer I've created a function that uses timeout and asynchronous Task classes instead of event handlers. According to Mike Adelson

Unfortunately, this method(event handlers) provides no way to know when the last bit of data has been received. Because everything is asynchronous, it is possible (and I have observed this) for events to fire after WaitForExit() has returned.

function Invoke-Executable {
# from https://stackoverflow.com/a/24371479/52277
    # Runs the specified executable and captures its exit code, stdout
    # and stderr.
    # Returns: custom object.
# from http://www.codeducky.org/process-handling-net/ added timeout, using tasks
param(
        [Parameter(Mandatory=$true)]
        [ValidateNotNullOrEmpty()]
        [String]$sExeFile,
        [Parameter(Mandatory=$false)]
        [String[]]$cArgs,
        [Parameter(Mandatory=$false)]
        [String]$sVerb,
        [Parameter(Mandatory=$false)]
        [Int]$TimeoutMilliseconds=1800000 #30min
    )
    Write-Host $sExeFile $cArgs

    # Setting process invocation parameters.
    $oPsi = New-Object -TypeName System.Diagnostics.ProcessStartInfo
    $oPsi.CreateNoWindow = $true
    $oPsi.UseShellExecute = $false
    $oPsi.RedirectStandardOutput = $true
    $oPsi.RedirectStandardError = $true
    $oPsi.FileName = $sExeFile
    if (! [String]::IsNullOrEmpty($cArgs)) {
        $oPsi.Arguments = $cArgs
    }
    if (! [String]::IsNullOrEmpty($sVerb)) {
        $oPsi.Verb = $sVerb
    }

    # Creating process object.
    $oProcess = New-Object -TypeName System.Diagnostics.Process
    $oProcess.StartInfo = $oPsi


    # Starting process.
    [Void]$oProcess.Start()
# Tasks used based on http://www.codeducky.org/process-handling-net/    
 $outTask = $oProcess.StandardOutput.ReadToEndAsync();
 $errTask = $oProcess.StandardError.ReadToEndAsync();
 $bRet=$oProcess.WaitForExit($TimeoutMilliseconds)
    if (-Not $bRet)
    {
     $oProcess.Kill();
    #  throw [System.TimeoutException] ($sExeFile + " was killed due to timeout after " + ($TimeoutMilliseconds/1000) + " sec ") 
    }
    $outText = $outTask.Result;
    $errText = $errTask.Result;
    if (-Not $bRet)
    {
        $errText =$errText + ($sExeFile + " was killed due to timeout after " + ($TimeoutMilliseconds/1000) + " sec ") 
    }
    $oResult = New-Object -TypeName PSObject -Property ([Ordered]@{
        "ExeFile"  = $sExeFile;
        "Args"     = $cArgs -join " ";
        "ExitCode" = $oProcess.ExitCode;
        "StdOut"   = $outText;
        "StdErr"   = $errText
    })

    return $oResult
}
Community
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Michael Freidgeim
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    Thanks for sharing! Using milliseconds for timeout in a PowerShell script is probably overkill. I cannot imagine a script where such precision would be required and even if I could, I'm not sure PS is up to the task. Otherwise it's indeed a better approach. I wrote my function before I dived into C# deep enough to fully understand how async worked in .NET but now it's time to review and take it up a notch. – Alexander Obersht Apr 12 '16 at 16:38
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    You know of a way to split the stream? I want to allow for either/both of write and capture. That way progress could be written to the console so that the user can see whats going on live, AND the output could be captured so that other stops down the pipeline can process it. – Lucas Mar 03 '17 at 21:29
  • many thanks, it helped me a lot now with my PowerShell scripts and a hung process situation we had at the company ! – R13mus Sep 18 '20 at 12:08
4

I couldn't get either of these examples to work with PS 4.0.

I wanted to run puppet apply from an Octopus Deploy package (via Deploy.ps1) and see the output in "real time" rather than wait for the process to finish (an hour later), so I came up with the following:

# Deploy.ps1

$procTools = @"

using System;
using System.Diagnostics;

namespace Proc.Tools
{
  public static class exec
  {
    public static int runCommand(string executable, string args = "", string cwd = "", string verb = "runas") {

      //* Create your Process
      Process process = new Process();
      process.StartInfo.FileName = executable;
      process.StartInfo.UseShellExecute = false;
      process.StartInfo.CreateNoWindow = true;
      process.StartInfo.RedirectStandardOutput = true;
      process.StartInfo.RedirectStandardError = true;

      //* Optional process configuration
      if (!String.IsNullOrEmpty(args)) { process.StartInfo.Arguments = args; }
      if (!String.IsNullOrEmpty(cwd)) { process.StartInfo.WorkingDirectory = cwd; }
      if (!String.IsNullOrEmpty(verb)) { process.StartInfo.Verb = verb; }

      //* Set your output and error (asynchronous) handlers
      process.OutputDataReceived += new DataReceivedEventHandler(OutputHandler);
      process.ErrorDataReceived += new DataReceivedEventHandler(OutputHandler);

      //* Start process and handlers
      process.Start();
      process.BeginOutputReadLine();
      process.BeginErrorReadLine();
      process.WaitForExit();

      //* Return the commands exit code
      return process.ExitCode;
    }
    public static void OutputHandler(object sendingProcess, DataReceivedEventArgs outLine) {
      //* Do your stuff with the output (write to console/log/StringBuilder)
      Console.WriteLine(outLine.Data);
    }
  }
}
"@

Add-Type -TypeDefinition $procTools -Language CSharp

$puppetApplyRc = [Proc.Tools.exec]::runCommand("ruby", "-S -- puppet apply --test --color false ./manifests/site.pp", "C:\ProgramData\PuppetLabs\code\environments\production");

if ( $puppetApplyRc -eq 0 ) {
  Write-Host "The run succeeded with no changes or failures; the system was already in the desired state."
} elseif ( $puppetApplyRc -eq 1 ) {
  throw "The run failed; halt"
} elseif ( $puppetApplyRc -eq 2) {
  Write-Host "The run succeeded, and some resources were changed."
} elseif ( $puppetApplyRc -eq 4 ) {
  Write-Warning "WARNING: The run succeeded, and some resources failed."
} elseif ( $puppetApplyRc -eq 6 ) {
  Write-Warning "WARNING: The run succeeded, and included both changes and failures."
} else {
  throw "Un-recognised return code RC: $puppetApplyRc"
}

Credit goes to T30 and Stefan Goßner

Community
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KingBob
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  • Thank! The only example which works really asynchronously. To make it works even better i'v also added: for non-english letters from kubectl and other binaries with non-bom output - `process.StartInfo.StandardOutputEncoding = System.Text.Encoding.GetEncoding("UTF-8")` . kill process on pwsh exit - `AppDomain.CurrentDomain.ProcessExit += (a, b) => process.Kill();` kill process on ctrl+c - `Console.CancelKeyPress += (a, b) => process.Kill(); ` – Anton Smolkov Nov 02 '20 at 07:34
  • @AntonSmolkov I'm guessing this works asynchronously because the WaitForExit method is in the dll code. You can do it in pure PS by replacing the WaitForExit with a while loop on !$process.HasExited and sleeping. – Blaisem Oct 11 '22 at 15:27
2

The examples here are all useful, but didn't completely suit my use case. I didn't want to invoke the command and exit. I wanted to open a command prompt, send input, read the output, and repeat. Here's my solution for that.

Create Utils.CmdManager.cs

using System;
using System.Diagnostics;
using System.Text;
using System.Threading;

namespace Utils
{
    public class CmdManager : IDisposable
    {
        const int DEFAULT_WAIT_CHECK_TIME = 100;
        const int DEFAULT_COMMAND_TIMEOUT = 3000;

        public int WaitTime { get; set; }
        public int CommandTimeout { get; set; }

        Process _process;
        StringBuilder output;

        public CmdManager() : this("cmd.exe", null, null) { }
        public CmdManager(string filename) : this(filename, null, null) { }
        public CmdManager(string filename, string arguments) : this(filename, arguments, null) { }

        public CmdManager(string filename, string arguments, string verb)
        {
            WaitTime = DEFAULT_WAIT_CHECK_TIME;
            CommandTimeout = DEFAULT_COMMAND_TIMEOUT;

            output = new StringBuilder();

            _process = new Process();
            _process.StartInfo.FileName = filename;
            _process.StartInfo.RedirectStandardInput = true;
            _process.StartInfo.RedirectStandardOutput = true;
            _process.StartInfo.RedirectStandardError = true;
            _process.StartInfo.CreateNoWindow = true;
            _process.StartInfo.UseShellExecute = false;
            _process.StartInfo.ErrorDialog = false;
            _process.StartInfo.Arguments = arguments != null ? arguments : null;
            _process.StartInfo.Verb = verb != null ? verb : null;

            _process.EnableRaisingEvents = true;
            _process.OutputDataReceived += (s, e) =>
            {
                lock (output)
                {
                    output.AppendLine(e.Data);
                };
            };
            _process.ErrorDataReceived += (s, e) =>
            {
                lock (output)
                {
                    output.AppendLine(e.Data);
                };
            };

            _process.Start();
            _process.BeginOutputReadLine();
            _process.BeginErrorReadLine();
            _process.StandardInput.AutoFlush = true;
        }

        public void RunCommand(string command)
        {
            _process.StandardInput.WriteLine(command);
        }

        public string GetOutput()
        {
            return GetOutput(null, CommandTimeout, WaitTime);
        }

        public string GetOutput(string endingOutput)
        {
            return GetOutput(endingOutput, CommandTimeout, WaitTime);
        }

        public string GetOutput(string endingOutput, int commandTimeout)
        {
            return GetOutput(endingOutput, commandTimeout, WaitTime);
        }

        public string GetOutput(string endingOutput, int commandTimeout, int waitTime)
        {
            string tempOutput = "";
            int tempOutputLength = 0;
            int amountOfTimeSlept = 0;

            // Loop until
            //  a) command timeout is reached
            //  b) some output is seen
            while (output.ToString() == "")
            {
                if (amountOfTimeSlept >= commandTimeout)
                {
                    break;
                }

                Thread.Sleep(waitTime);
                amountOfTimeSlept += waitTime;
            }

            // Loop until:
            //  a) command timeout is reached
            //  b) endingOutput is found
            //  c) OR endingOutput is null and there is no new output for at least waitTime
            while (amountOfTimeSlept < commandTimeout)
            {
                if (endingOutput != null && output.ToString().Contains(endingOutput))
                {
                    break;
                }
                else if(endingOutput == null && tempOutputLength == output.ToString().Length)
                {
                    break;
                }

                tempOutputLength = output.ToString().Length;

                Thread.Sleep(waitTime);
                amountOfTimeSlept += waitTime;
            }

            // Return the output and clear the buffer
            lock (output)
            {
                tempOutput = output.ToString();
                output.Clear();
                return tempOutput.TrimEnd();
            }
        }

        public void Dispose()
        {
            _process.Kill();
        }
    }
}

Then from PowerShell add the class and use it.

Add-Type -Path ".\Utils.CmdManager.cs"

$cmd = new-object Utils.CmdManager
$cmd.GetOutput() | Out-Null

$cmd.RunCommand("whoami")
$cmd.GetOutput()

$cmd.RunCommand("cd")
$cmd.GetOutput()

$cmd.RunCommand("dir")
$cmd.GetOutput()

$cmd.RunCommand("cd Desktop")
$cmd.GetOutput()

$cmd.RunCommand("cd")
$cmd.GetOutput()

$cmd.RunCommand("dir")
$cmd.GetOutput()

$cmd.Dispose()

Don't forget to call the Dispose() function at the end to clean up the process that is running in the background. Alternatively, you could close that process by running something like $cmd.RunCommand("exit")

Elijah W. Gagne
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1

I came here looking for a solution to create a wrapper that logs the process, and outputs it to screen. None of these worked for me. I made this code, which seemed to work fine.

The PSDataCollection allows you to continue out with your script, without having to wait for process to complete.

Using namespace System.Diagnostics;
Using namespace System.Management.Automation;

$Global:Dir = Convert-Path "."
$Global:LogPath = "$global:Dir\logs\mylog.log"
[Process]$Process = [Process]::New();
[ProcessStartInfo]$info = [ProcessStartInfo]::New();
$info.UseShellExecute = $false
$info.Verb = "runas"
$info.WorkingDirectory = "$Global:Dir\process.exe"
$info.FileName = "$Global:Dir\folder\process.exe"
$info.Arguments = "-myarg yes -another_arg no"
$info.RedirectStandardOutput = $true
$info.RedirectStandardError  = $true
$Process.StartInfo = $info;
$Process.EnableRaisingEvents = $true
$Global:DataStream = [PSDataCollection[string]]::New()
$Global:DataStream.add_DataAdded(
    {
        $line = $this[0];
        [IO.File]::AppendAllLines($LogPath, [string[]]$line);
        [Console]::WriteLine($line)
        $this.Remove($line);
    }
)
$script = {
    param([Object]$sender, [DataReceivedEventArgs]$e) 
    $global:Datastream.Add($e.Data)
}
Register-ObjectEvent -InputObject $Process -Action $script -EventName 'OutputDataReceived' | Out-Null
Register-ObjectEvent -InputObject $Process -Action $script -EventName 'ErrorDataReceived' | Out-Null
$Process.Start()
$Process.BeginOutputReadLine()
$Process.BeginErrorReadLine()
Jacob Kucinic
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0

If you just want to dynamically dump it to the PowerShell console do this:

my.exe | Out-Default

I can't claim to have figured it out.

See the bottom of this technet post: https://social.technet.microsoft.com/Forums/windowsserver/en-US/b6691fba-0e92-4e9d-aec2-47f3d5a17419/start-process-and-redirect-output-to-powershell-window?forum=winserverpowershell

which also refers to this stackoverflow post.

$LASTEXITCODE was also populated with the exit code from my exe which was also what I needed.

Maximojo
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  • This only works if you are calling the process natively. A more customizable form of calling is via `Start-Process / [System.Diagnostics.Process]`, which create an object that will **not** return the process output when piped. – Blaisem Oct 11 '22 at 11:32
0

I came across this thread and would like to share my solution for whomever may need this in the future. This was working on PowerShell Core 7.3.4.

<#
.Synopsis
    This function will run a provided command and arguments.
.DESCRIPTION
    This function was created due to the inconsistencies of running Start-Process in Linux. This function provides a 
    consistent way of running non-PowerShell commands that require many parameters/arguments to run (e.g., docker).
    
    PowerShell commands or aliases will NOT work with this function. For example commands such as: echo, history, or cp
    will NOT work. Use the build-in PowerShell commands for those.
.PARAMETER Name
    The path or name of the command to be ran.
.PARAMETER Arguments
    The optional parameters/arguments to be added with your command.
.PARAMETER WorkingDirectory
    The current WorkingDirectory to run said Command. If you are not using the full path to files, you should probably
    use this parameter. 
.PARAMETER LoadUserProfile
    Gets or sets a value that indicates whether the Windows user profile is to be loaded from the registry.

    This will NOT work on Unix/Linux.
.PARAMETER Timer
    Provide a timer (in ms) for how long you want to wait for the process to exit/end.
.PARAMETER Verb
    Specifies a verb to use when this cmdlet starts the process. The verbs that are available are determined by the filename extension of the file that runs in the process.

    The following table shows the verbs for some common process file types.

    File type   Verbs
    .cmd    Edit, Open, Print, RunAs, RunAsUser
    .exe    Open, RunAs, RunAsUser
    .txt    Open, Print, PrintTo
    .wav    Open, Play
    To find the verbs that can be used with the file that runs in a process, use the New-Object cmdlet to create a System.Diagnostics.ProcessStartInfo object for the file. The available verbs are in the Verbs property of the ProcessStartInfo object. For details, see the examples.

    This will NOT work on Unix/Linux.
.PARAMETER Passthru
    Pass the object into the pipeline. Using -Passthru will ignore error-handling.
.NOTES
    Author - Zack Flowers
.LINK
    GitHub: https://github.com/zackshomelab
.EXAMPLE
    Start-Command -Name 'docker' -CommandArguments "container ls --all"
    
    Example #1:
    This example executes command 'docker' and passes arguments 'container ls --all' to display the offline/online containers.
.EXAMPLE
    Start-Command -Name 'docker' -CommandArguments "container", "ls", "--all"

    Example #2:
    This example is simular to Example #1, except it accepts comma-separated arguments.
.EXAMPLE
    $whoami = Start-Command -Name 'whoami' -Passthru

    $whoami

    Title        : whoami
    OutputStream : System.Management.Automation.PSEventJob
    OutputData   : zac
    ErrorStream  : 
    ErrorData    : 
    ExitCode     : 0

    Example #3:
    This example utilizes the -Passthru feature of this script.
.INPUTS
    None
.OUTPUTS
    System.String
    System.Management.Automation.PSCustomObject
#>
function Start-Command {
    [cmdletbinding(DefaultParameterSetName="default")]
    param (
        [parameter(Mandatory,
            Position=0,
            ValueFromPipelineByPropertyName)]
            [ValidateNotNullOrEmpty()]
        [string]$Name,

        [parameter(Mandatory=$false,
            Position=1,
            ValueFromPipelineByPropertyName)]
            [ValidateNotNullOrEmpty()]
        [object]$Arguments,

        [parameter(Mandatory=$false,
            ValueFromPipelineByPropertyName)]
            [ValidateScript({Test-Path $_})]
        [string]$WorkingDirectory,

        [parameter(Mandatory=$false)]
            [ValidateScript({
                if ($PSVersionTable.Platform -eq "Unix") {
                    Throw "-LoadUserProfile cannot be used on Unix/Linux."
                }
            })]
        [switch]$LoadUserProfile,

        [parameter(Mandatory,
            ValueFromPipelineByPropertyName,
            ParameterSetName="timer")]
            [ValidateRange(1, 600000)]
        [int]$Timer,

        [parameter(Mandatory=$false,
            ValueFromPipelineByPropertyName)]
            [ValidateScript({
                if ($PSVersionTable.Platform -eq "Unix") {
                    Throw "-Verb cannot be used on Unix/Linux."
                }
            })]
        [string]$Verb,

        [parameter(Mandatory=$false)]
        [switch]$Passthru
    )

    begin {
        $FileName = (Get-Command -Name $Name -ErrorAction SilentlyContinue).Source

        # If we cannot find the provided FileName, this could be due to the user providing..
        # ..a command that is a PowerShell Alias (e.g., echo, history, cp)
        if ($null -eq $FileName -or $FileName -eq "") {
            
            # Source doesn't exist. Let's see if the provided command is a PowerShell command
            $getPSCommand = (Get-Command -Name $Name -ErrorAction SilentlyContinue)

            if ($null -eq $getPSCommand -or $getPSCommand -eq "") {
                Throw "Start-Command: Could not find command $Name nor could we find its PowerShell equivalent."
            }

            # Stop the script if the command was found but it returned an alias. 
            # Sometimes, a command may not return a source but WILL return an alias. This will cause issues with incompatibility with..
            # ..parameters for said commands.
            #
            # Example commands that will not work: echo, history, and cd
            if ($getPSCommand.CommandType -eq 'Alias') {
                Throw "Start-Command: This function does not support Aliases. Command $Name matches $($getPSCommand.ResolvedCommand.Name)."
            }

            # This function does not support Microsoft PowerShell commands.
            if ($getPSCommand.Source -like "Microsoft.PowerShell*") {
                Throw "Start-Command: This function should only be used for Non-PowerShell commands (e.g., wget, touch, mkdir, etc.)"
            }

            # Retrieve the version of PowerShell and its location and replace $FileName with it
            $FileName = $PSVersionTable.PSEdition -eq 'Core' ? (Get-Command -Name 'pwsh').Source : (Get-Command -Name 'powershell').Source
            
            # Reconfigure Arguments to execute PowerShell
            $Arguments = "-noprofile -Command `"& {$($getPSCommand.ReferencedCommand.Name) $Arguments}`""
        }

        # Data Object will store all streams of data from our command
        $dataObject = [pscustomobject]@{
            Title        = $Name
            OutputStream = ''
            OutputData   = ''
            ErrorData    = ''
            ExitCode     = 0
        }
    }
    process {

        $processStartInfoProps = @{
            Arguments               = $null -ne $Arguments ? $Arguments : $null
            CreateNoWindow          = $true
            ErrorDialog             = $false
            FileName                = $FileName
            RedirectStandardError   = $true
            RedirectStandardInput   = $true
            RedirectStandardOutput  = $true
            UseShellExecute         = $false
            WindowStyle             = [System.Diagnostics.ProcessWindowStyle]::Hidden
            WorkingDirectory        = $PSBoundParameters.ContainsKey('WorkingDirectory') ? $WorkingDirectory : $PSScriptRoot
            Verb                    = $PSBoundParameters.ContainsKey('Verb') ? $Verb : $null
        }

        # This will Error on Unix/Linux Systems if property LoadUserProfile is added regardless if it's null or false.
        if ($PSBoundParameters.ContainsKey('LoadUserProfile')) {
            $processStartInfoProps.Add('LoadUserProfile', $LoadUserProfile)
        }

        try {

            $process = New-Object System.Diagnostics.Process
            $process.EnableRaisingEvents = $true

            $processStartInfo = New-Object System.Diagnostics.ProcessStartInfo -Property $processStartInfoProps
            $process.StartInfo = $processStartInfo

            # Register Process OutputDataReceived:
            #   This will create a background job to capture output data
            #   Reference: https://learn.microsoft.com/en-us/dotnet/api/system.diagnostics.process.standardoutput?redirectedfrom=MSDN&view=net-7.0#System_Diagnostics_Process_StandardOutput
            $outputEventParams = @{
                InputObject = $process
                SourceIdentifier = 'OnOutputDataReceived '
                EventName = 'OutputDataReceived'
                Action = {
                    param (
                        [System.Object]$sender,
                        [System.Diagnostics.DataReceivedEventArgs]$e
                    )

                    foreach ($data in $e.Data) { 
                        if ($null -ne $data -and $data -ne "") { 
                            $($data).Trim()
                        } 
                    }
                }
            }
            $dataObject.OutputStream = Register-ObjectEvent @outputEventParams

            # Start the process/command
            if ($process.Start()) {
                $process.BeginOutputReadLine()
                $dataObject.ErrorData = $process.StandardError.ReadToEnd()

                if ($PSCmdlet.ParameterSetName -eq 'timer') {
                    $process.WaitForExit($Timer) | Out-Null
                } else {
                    $process.WaitForExit()
                }
            }
            
            # Retrieve the exit code and the OutputStream Job
            $dataObject.ExitCode = $process.ExitCode
            $dataObject.OutputData = Receive-Job -id $($dataObject.OutputStream.id)

            [bool]$hasError = ($null -ne $($dataObject.ErrorData) -and $($dataObject.ErrorData) -ne "" -and $($dataObject.ExitCode) -ne 0) ? $true : $false
            [bool]$hasOutput = ($null -ne $($dataObject.OutputData) -and $($dataObject.OutputData) -ne "") ? $true : $false

            # Output the PSCustomObject if -Passthru is provided.
            if ($Passthru) {
                if ($hasError) {
                    $dataObject.ErrorData = $($dataObject.ErrorData.Trim())
                }
                $dataObject
            } else {

                if ($hasError) {
                    if ($($ErrorActionPreference) -ne 'Stop') {
                        Write-Error "Exit Code $($dataObject.ExitCode): $($dataObject.ErrorData.Trim())"
                    } else {
                        Throw "Exit Code $($dataObject.ExitCode): $($dataObject.ErrorData.Trim())"
                    }
                }

                if ($hasOutput) {
                    $($dataObject.OutputData)
                }
            }
        }
        finally {

            # Cleanup
            $process.Close()
            Unregister-Event -SourceIdentifier $($dataObject.OutputStream.Name) -Force | Out-Null
            Remove-Job -Id $($dataObject.OutputStream.Id) -Force
        }
    }
}

Example 1: Regular Usage

Start-Command -Name 'docker' -Arguments 'container ls --all'

Example 2: Comma-Separated Arguments

Start-Command -Name 'docker' -Arguments 'container', 'ls', '--all'

Example 3: Passthru Usage

$whoami = Start-Command -Name 'whoami' -Passthru

$whoami

Title        : whoami
OutputStream : System.Management.Automation.PSEventJob
OutputData   : zac
ErrorStream  : 
ErrorData    : 
ExitCode     : 0

Example 4: Error Example

Start-Command -Name 'docker' -Arguments 'force' -ErrorAction Stop

Output: 
Line |
 245 |  …             Throw "Exit Code $($dataObject.ExitCode): $($dataObject.E …
     |                ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     | Exit Code 1: docker: 'force' is not a docker command. See 'docker --help'
ZHL-Zack
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