Implemented commands until helloworld works \o/

pkg/pointer/intput-output.go

@@ -0,0 +1,61 @@
+package pointer
+
+import (
+	"fmt"
+	"log"
+	"os"
+
+	"github.com/pkg/term"
+)
+
+var defaultInputLastChar *int = nil
+
+func DefaultCharacterInput() int {
+	if defaultInputLastChar != nil {
+		c := *defaultInputLastChar
+		defaultInputLastChar = nil
+		return c
+	}
+	t, err := term.Open("/dev/stdin")
+	if err != nil {
+		log.Fatalf("Could not open stdin: %+v", err)
+	}
+	defer t.Close()
+	defer t.Restore()
+	term.RawMode(t)
+	b := make([]byte, 1)
+	i, err := os.Stdin.Read(b)
+	if err != nil {
+		log.Fatalf("Error in DefaultCharacterInput { b: %c, i: %d, err: %+v }", b[0], i, err)
+	}
+	return int(b[0])
+}
+
+func DefaultDecimalInput() int {
+	var v int
+	for {
+		c := DefaultCharacterInput()
+		if c >= '0' && c <= '9' {
+			v = c - '0'
+			break
+		}
+	}
+	for {
+		c := DefaultCharacterInput()
+		if c >= '0' && c <= '9' {
+			v = v*10 + c - '0'
+		} else {
+			defaultInputLastChar = &c
+			break
+		}
+	}
+	return v
+}
+
+func DefaultCharacterOutput(c int) {
+	fmt.Printf("%c", c)
+}
+
+func DefaultDecimalOutput(c int) {
+	fmt.Printf("%d ", c)
+}