Apply a JS Link file to all document library in all site of a site collection

jslinktoalldocumentlibrary.ps1

#Load powershell snapin
Add-PSSnapin "Microsoft.SharePoint.PowerShell"
#Get site collection details
$site = Get-SPSite http://mysite
#Get all web sites in the site collections
$websites = $s.AllWebs
foreach($website in $websites)
{
	Write-Host $website.Title -foreground Yellow

	#loopthrouh the lists and libraries in the site
	foreach($l in $website.Lists)
  	{
		#Check for only document libraries
		if($l.BaseTemplate -eq "DocumentLibrary" -and $l.Title -ne "Site Assets")
		{
			Write-Host "Processing " + $l.RootFolder.Name + " ..." -foreground Green
			$webPartPage = $l.RootFolder.Name + "/Forms/AllItems.aspx"
			Write-Host $webPartPage + " OK" -foreground Gray
			$file = $website.GetFile($webPartPage)
			#$file.CheckOut()
 
			$webPartManager = $website.GetLimitedWebPartManager($webPartPage, [System.Web.UI.WebControls.WebParts.PersonalizationScope]::Shared)
 
			$webpart = $webPartManager.WebParts[0]
 
			$webpart.JSLink = "~SiteCollection/_catalogs/masterpage/linkfile.js"
 
			$webPartManager.SaveChanges($webpart)
 
			#$file.CheckIn("Awesomeness has been delivered")
		}
	}
}