How to tail log files in Powershell for particular string - powershell

Question

We would like to tail several log files "live" in powershell for particular string. We have tried to use "get-content" command but without luck because everytime as a result we received only results from one file. I assume that it was caused by "-wait" parameter. If there is any other way to tail multiple files ? I heard about runspaces but still I don't know how to implement it.
Our sample script below
dir d:\test\*.txt -include *.txt | `
Get-Content -Wait | `
select-string "windows" | `
ForEach-Object {Write-EventLog -LogName Application -Source "Application error" -EntryType information -EventId 999 -Message $_}
Any help will be appreciated.

Answer 1

Might be slightly late to the party...
As per here, we can use the following in a .ps1 file;
$ProgressPreference='SilentlyContinue'
Workflow My-Tail
{
Param([string[]] $Path)
foreach -parallel ($file in $path)
{
Get-Content -Path $file -Tail 1 -Wait
}
}
This lets us tail multiple files, invoking in powershell like;
My-Tail (dir C:\Users\User\Documents\*.log)
All that's left then is to filter by the required string;
My-Tail (dir C:\Users\User\Documents\*.log) | Select-String -Pattern ".*ERROR.*"
This will tail all files ending in .log in Documents, outputting lines that contain the text 'ERROR'

Answer 2

The only way I can think to do this is to create a bunch of jobs that run the command on each file. You can then receive the job output in a loop and changes in any of the files will be written to the screen:
gci d:\test\*.txt | % { $sb = [scriptblock]::create("get-content -wait $_") ; start-job -ScriptBlock $sb }
while(1) {
$m = $(get-job | receive-job | select-string "searchstring")
if($m -ne $null) {
Write-EventLog -LogName Application -Source "Application error" -EntryType information -EventId 999 -Message $m
}
sleep 1
}