A simple CreateProcess wrapper for demonstrating starting a process with custom command-line arguments.

CreateProcess.ps1

function Start-ProcessWithCommandLine {
<#
.SYNOPSIS

A simple CreateProcess wrapper for demonstrating starting a process with custom command-line arguments.

Author: Matt Graeber
Company: Red Canary, Inc.

.PARAMETER ApplicationName

Specifies the path to the executable to start.

.PARAMETER CommandLine

Specifies a custom command-line for the application.

.EXAMPLE

Start-ProcessWithCommandLine

Starts a notepad.exe process with a "CustomCommandLineTest" command-line.

.EXAMPLE

Start-ProcessWithCommandLine -ApplicationName "$Env:windir\System32\WindowsPowerShell\v1.0\powershell.exe" -CommandLine 'Foo'
#>
    param (
        [Parameter(Position = 0)]
        [String]
        [ValidateNotNullOrEmpty()]
        $ApplicationName = "$Env:windir\System32\notepad.exe",

        [Parameter(Position = 0)]
        [String]
        [ValidateNotNullOrEmpty()]
        $CommandLine = 'CustomCommandLineTest'
    )

    $Source = @'
using System;
using System.Runtime.InteropServices;
using Microsoft.Win32.SafeHandles;

namespace CommandLineTest {
    public class NativeMethods {
        [StructLayout(LayoutKind.Sequential)]
		public class PROCESS_INFORMATION
		{
			public IntPtr hProcess = IntPtr.Zero;
			public IntPtr hThread = IntPtr.Zero;
			public int dwProcessId;
			public int dwThreadId;
		}

        [StructLayout(LayoutKind.Sequential)]
        public class STARTUPINFO
		{
			public int cb;
			public IntPtr lpReserved;
			public IntPtr lpDesktop;
			public IntPtr lpTitle;
			public int dwX;
			public int dwY;
			public int dwXSize;
			public int dwYSize;
			public int dwXCountChars;
			public int dwYCountChars;
			public int dwFillAttribute;
			public int dwFlags;
			public short wShowWindow;
			public short cbReserved2;
			public IntPtr lpReserved2;
			public IntPtr hStdInput;
			public IntPtr hStdOutput;
			public IntPtr hStdError;
		}

        [DllImport("kernel32.dll", BestFitMapping = false, CharSet = CharSet.Auto, SetLastError = true)]
		public static extern bool CreateProcess(
            string lpApplicationName,
            string lpCommandLine,
            IntPtr lpProcessAttributes,
            IntPtr lpThreadAttributes,
            bool bInheritHandles,
            int dwCreationFlags,
            IntPtr lpEnvironment,
            string lpCurrentDirectory,
            STARTUPINFO lpStartupInfo,
            PROCESS_INFORMATION lpProcessInformation);
    }
}
'@

    if (-not ('CommandLineTest.NativeMethods' -as [Type])) {
        Add-Type -TypeDefinition $Source
    }

    $StartupInfo = New-Object -TypeName CommandLineTest.NativeMethods+STARTUPINFO
    $StartupInfo.cb = [System.Runtime.InteropServices.Marshal]::SizeOf([Type][CommandLineTest.NativeMethods+STARTUPINFO])

    $ProcessInformation = New-Object -TypeName CommandLineTest.NativeMethods+PROCESS_INFORMATION

    $Result = [CommandLineTest.NativeMethods]::CreateProcess(
        $ApplicationName,   # lpApplicationName
        $CommandLine,       # lpCommandLine
        [IntPtr]::Zero,     # lpProcessAttributes
        [IntPtr]::Zero,     # lpThreadAttributes
        $True,              # bInheritHandles
        0x10,               # dwCreationFlags - CREATE_NEW_CONSOLE
        [IntPtr]::Zero,     # lpEnvironment
        $PWD.Path,          # lpCurrentDirectory
        $StartupInfo,       # lpStartupInfo
        $ProcessInformation # lpProcessInformation
    );$LastError = [ComponentModel.Win32Exception][Runtime.InteropServices.Marshal]::GetLastWin32Error()

    if ($Result) {
        $RunningProcessInfo = Get-CimInstance -ClassName Win32_Process -Property 'ExecutablePath', 'CommandLine' -Filter "ProcessId = $($ProcessInformation.dwProcessId)"

        [PSCustomObject] @{
            ProcessId = $ProcessInformation.dwProcessId
            ExecutablePath = $RunningProcessInfo.ExecutablePath
            CommandLine = $RunningProcessInfo.CommandLine
        }
    } else {
        Write-Error -Exception $LastError
    }
}