Fixes #50

ethereum/repl_darwin.go

 package main
 
+// #cgo darwin CFLAGS: -I/usr/local/opt/readline/include
+// #cgo darwin LDFLAGS: -L/usr/local/opt/readline/lib
 // #cgo LDFLAGS: -lreadline
 // #include <stdio.h>
 // #include <stdlib.h>
 // #include <readline/readline.h>
 // #include <readline/history.h>
 import "C"
-
 import (
+	"os"
+	"os/signal"
 	"strings"
+	"syscall"
 	"unsafe"
 )
 
+func initReadLine() {
+	C.rl_catch_sigwinch = 0
+	c := make(chan os.Signal, 1)
+	signal.Notify(c, syscall.SIGWINCH)
+	go func() {
+		for sig := range c {
+			switch sig {
+			case syscall.SIGWINCH:
+				C.rl_resize_terminal()
+			default:
+
+			}
+		}
+	}()
+}
+
 func readLine(prompt *string) *string {
 	var p *C.char
 
@@ -59,6 +79,7 @@ func (self *JSRepl) setIndent() {
 }
 
 func (self *JSRepl) read() {
+	initReadLine()
 L:
 	for {
 		switch result := readLine(&self.prompt); true {