first commit

.gitignore

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+.idea

main.go

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+package main
+
+import (
+	"fmt"
+	"os"
+	"syscall"
+	"time"
+
+	"github.com/warthog618/gpiod"
+	"github.com/warthog618/gpiod/device/rpi"
+)
+
+// Watches GPIO 4 (Raspberry Pi J8-7) and reports when it changes state.
+func main() {
+	c, err := gpiod.NewChip("gpiochip0")
+	if err != nil {
+		panic(err)
+	}
+	defer c.Close()
+
+	offset := rpi.J8p7
+	l, err := c.RequestLine(offset,
+		gpiod.WithPullUp,
+		gpiod.WithBothEdges(func(evt gpiod.LineEvent) {
+			t := time.Now()
+			edge := "rising"
+			if evt.Type == gpiod.LineEventFallingEdge {
+				edge = "falling"
+			}
+			fmt.Printf("event:%3d %-7s %s (%s)\n",
+				evt.Offset,
+				edge,
+				t.Format(time.RFC3339Nano),
+				evt.Timestamp)
+		}))
+	if err != nil {
+		fmt.Printf("RequestLine returned error: %s\n", err)
+		if err == syscall.Errno(22) {
+			fmt.Println("Note that the WithPullUp option requires kernel V5.5 or later - check your kernel version.")
+		}
+		os.Exit(1)
+	}
+	defer l.Close()
+
+	// In a real application the main thread would do something useful.
+	// But we'll just run for a minute then exit.
+	fmt.Printf("Watching Pin %d...\n", offset)
+	time.Sleep(time.Minute)
+	fmt.Println("exiting...")
+}