CLI example in a single commit (replaced tabs with spaces too)

examples/cli/cli.go

@@ -0,0 +1,96 @@
+/*
+
+An example of CLI by @vodolaz095, using the go-rpio library
+Usage Setting Pin 11 to High: ./gpiocli -p 11 -s=+1
+Setting Pin 11 to Low: ./gpiocli -p 11 -s=-1
+
+*/
+package main
+
+import (
+    "flag"
+    "fmt"
+    "github.com/stianeikeland/go-rpio"
+    "os"
+    "runtime"
+)
+
+func main() {
+    var (
+        pinNumber = flag.Int("p", 0, " number of pin to use")
+        high = flag.Bool("h", false, " return 0 if value is HIGH, omit to set value")
+        low = flag.Bool("l", false, " return 0 if value is LOW, omit to set value")
+        set = flag.Int("s", 0, " set pin value to high(1) or low(-1)")
+    )
+
+    flag.Parse()
+
+    if os.Geteuid() != 0 {
+        fmt.Println("This program have to be run as root, or SUID/GUID set to 0 on execution!")
+        os.Exit(1)
+    }
+
+    if runtime.GOARCH != "arm" {
+        fmt.Println("This program can be unpredictable on other machines rather than Raspberry Pi")
+        os.Exit(1)
+    }
+
+    if runtime.GOOS != "linux" {
+        fmt.Println("This program have to be executed on linux only!")
+        os.Exit(1)
+    }
+
+    // Open and map memory to access gpio, check for errors
+    if err := rpio.Open(); err != nil {
+        fmt.Println(err)
+        os.Exit(1)
+    }
+
+    // Unmap gpio memory when done
+    defer rpio.Close()
+
+    if *pinNumber == 0 {
+        fmt.Println("Set the pin number to use!")
+        os.Exit(1)
+    } else {
+        if *high || *low {
+            //we get the value for pin
+            pin := rpio.Pin(*pinNumber)
+            pin.Input() // Input mode
+            res := pin.Read()
+            fmt.Printf("Raspberry PI GPIO status for pin #%d - %d\n", *pinNumber, pin.Read())
+            if *high {
+                if res == rpio.High {
+                    os.Exit(0)
+                } else {
+                    os.Exit(1)
+                }
+            } else {
+                if res == rpio.Low {
+                    os.Exit(0)
+                } else {
+                    os.Exit(1)
+                }
+            }
+        } else {
+            switch *set {
+            case 1:
+                pin := rpio.Pin(*pinNumber)
+                pin.Output() // Output mode
+                pin.High()
+                os.Exit(0)
+                break
+            case -1:
+                //we set the value for pin
+                pin := rpio.Pin(*pinNumber)
+                pin.Output() // Output mode
+                pin.Low()
+                os.Exit(0)
+                break
+            default:
+                flag.PrintDefaults()
+                os.Exit(1)
+            }
+        }
+    }
+}