Add network device driver model, netdev

examples/net/http-head/main.go

@@ -0,0 +1,57 @@
+// This example gets an URL using http.Head().  URL scheme can be http or https.
+//
+// Note: It may be necessary to increase the stack size when using "net/http".
+// Use the -stack-size=4KB command line option.
+//
+// Some targets (Arduino Nano33 IoT) don't have enough SRAM to run http.Head().
+// Use the following for those targets:
+//
+//     examples/net/webclient (for HTTP)
+//     examples/net/tlsclient (for HTTPS)
+
+package main
+
+import (
+	"bytes"
+	"fmt"
+	"log"
+	"machine"
+	"net/http"
+	"time"
+)
+
+var (
+	ssid string
+	pass string
+	url  string = "https://httpbin.org"
+)
+
+func main() {
+
+	waitSerial()
+
+	if err := netdev.NetConnect(); err != nil {
+		log.Fatal(err)
+	}
+
+	resp, err := http.Head(url)
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer resp.Body.Close()
+
+	var buf bytes.Buffer
+	if err := resp.Write(&buf); err != nil {
+		log.Fatal(err)
+	}
+	fmt.Println(string(buf.Bytes()))
+
+	netdev.NetDisconnect()
+}
+
+// Wait for user to open serial console
+func waitSerial() {
+	for !machine.Serial.DTR() {
+		time.Sleep(100 * time.Millisecond)
+	}
+}