Using PowerShell to watch a log

I was recently troubleshooting an issue and needed to view the last few results of a log. CMTrace and text editors would crash due to the sheer size of the log. Powershell’s Get-Content with the “Tail” parameter worked like a charm however. Although this worked, I didn’t want to keep running the command over and over, so, I decided to replicate the watch command from Linux in PowerShell.

<#
.SYNOPSIS
    Repetitively runs a script block to allow you to track changes in the command output. An example use would be for watching log inputs. Press CTRL+C to cancel script. It runs indefinitely.

.PARAMETER ScriptBlock
    Script to execute

.PARAMETER Interval
    How often to rerun scriptblock in seconds

.NOTES
    Version:        1.0
    Author:         Matthew Thompson
    Creation Date:  2017-07-19
    Purpose/Change: Initial script development
  
.EXAMPLE
    &"Start-Watch.ps1" -ScriptBlock {Get-Content -Path "C:\Logs\SomeLog.log" -Tail 20} -Interval 10
#>
Param([scriptblock]$ScriptBlock, [int32]$Interval=5)
#Put the real code in a function so it can be quickly copy-pasted as a child function of other scripts
function Start-Watch
{
    Param([scriptblock]$ScriptBlock, [int32]$Interval)
    #Set lowest possible datetime, so that it will run script immediatly
    $Start = [DateTime]::MinValue
    #Infinite loop, cancel require user intervention (CTRL+C)
    while($true)
    {
        #If enough time has passed (Now - LastAttempt)>Selected interval
        if ([DateTime]::Now - $Start -ge [TimeSpan]::FromSeconds($Interval))
        {
            #Clear console and call function
            Clear-Host
            $ScriptBlock.Invoke()
            #Set new start time/last attempt
            $Start = [DateTime]::Now
        }
        #Sleep the thread, prevents CPU from falsly registering as 100% utilized
        [System.Threading.Thread]::Sleep(1)
    }
}
#Call watch function
Start-Watch -ScriptBlock $ScriptBlock -Interval $Interval