PowerShell script that starts specified applications if they are not currently running. Useful in conjuncftion with Windows Event Log triggered Scheduled Tasks to provide a simple process supervisor system.

sdr-monitor.ps1

# Use this as the "Start Program" Action for an "On an event -> Log - > Application -> Application Error" Scheduled Task
# To automatically restart applications in the $monitored_apps hash if they crash (and the crash is reported in the event log)
# 
# Setup scheduled task like documented @ https://www.reddit.com/r/windows/comments/4td55w/comment/d5gldsj/,
# except don't bother with Step 7 (keyword filtering) as it doesn't work as written there.
# Instead, delegate all process filtering to this script in the $monitored_apps hash below.
#
# Copyleft Ian Gallagher <crash@neg9.org>

# Applications to monitor and start if they are found to not be running (hash of Process fields Name and Path)
$monitored_apps = @{
    'PDW' = 'C:\pdw\PDW.exe'
    'SDR Console' = 'C:\Program Files\SDR-Radio.com (V3)\SDR Console.exe'
    'ProScan' = 'C:\ProScan\ProScan.exe'
}

# Sleep momentarily in case the crashed application is lingering
Start-Sleep -Seconds 1.0

# Loop over each item in the monitored_apps table, check if it's running, if not, start it
$started_processes = @()

foreach ($app in $monitored_apps.GetEnumerator())
{
    if (-Not (Get-Process | where name -eq $app.Key)) {
        $started_processes += Start-Process -FilePath "$($app.Value)" -PassThru
    }
}

foreach ($process in $started_processes) {
    $msg = "Started application '$($process.Name)' ($($process.Path)) as it was not running."
    Write-Host $msg
    Write-EventLog -LogName Application -Source sdr-supervisor -EntryType Information -Category 0 -EventId 1 -Message $msg
}

if ($started_processes.Count -eq 0) {
    $msg = "All expected applications are running ($($monitored_apps.Keys -Join ', '))"
    Write-Host $msg
    Write-EventLog -LogName Application -Source sdr-supervisor -EntryType Information -Category 0 -EventId 0 -Message $msg
}