Add an exec daemon plugin (#4424)

plugins/inputs/execd/examples/count.go

@@ -0,0 +1,24 @@
+package main
+
+// Example using HUP signaling
+
+import (
+	"fmt"
+	"os"
+	"os/signal"
+	"syscall"
+)
+
+func main() {
+	c := make(chan os.Signal, 1)
+	signal.Notify(c, syscall.SIGHUP)
+
+	counter := 0
+
+	for {
+		<-c
+
+		fmt.Printf("counter_go count=%d\n", counter)
+		counter++
+	}
+}

plugins/inputs/execd/examples/count.rb

@@ -0,0 +1,13 @@
+#!/usr/bin/env ruby
+
+## Example in Ruby not using any signaling
+
+counter = 0
+
+loop do
+  puts "counter_ruby count=#{counter}"
+  STDOUT.flush
+  counter += 1
+
+  sleep 1
+end

plugins/inputs/execd/examples/count.sh

@@ -0,0 +1,12 @@
+#!/bin/bash
+
+## Example in bash using STDIN signaling
+
+counter=0
+
+while read; do
+    echo "counter_bash count=${counter}"
+    let counter=counter+1
+done
+
+(>&2 echo "terminate")