shim improvements for docs, clean quit, and slow readers (#7452)

plugins/inputs/execd/shim/goshim_windows.go

@@ -3,11 +3,20 @@
 package shim
 
 import (
+	"context"
 	"os"
 	"os/signal"
 	"syscall"
 )
 
-func listenForCollectMetricsSignals(collectMetricsPrompt chan os.Signal) {
+func listenForCollectMetricsSignals(ctx context.Context, collectMetricsPrompt chan os.Signal) {
 	signal.Notify(collectMetricsPrompt, syscall.SIGHUP)
+
+	go func() {
+		select {
+		case <-ctx.Done():
+			// context done. stop to signals to avoid pushing messages to a closed channel
+			signal.Stop(collectMetricsPrompt)
+		}
+	}()
 }