Prepare for termbox/windows build

`TAGS=termbox make` (or `go build -tags termbox`)

3 files changed, 37 insertions, 14 deletions

diff --git a/src/util/util.go b/src/util/util.go
index e273882c..2a1607ce 100644
--- a/src/util/util.go
+++ b/src/util/util.go
@@ -1,13 +1,11 @@
 package util
 
-// #include <unistd.h>
-import "C"
-
 import (
 	"math"
 	"os"
-	"os/exec"
 	"time"
+
+	"github.com/junegunn/go-isatty"
 )
 
 // Max returns the largest integer
@@ -95,14 +93,5 @@ func DurWithin(
 
 // IsTty returns true is stdin is a terminal
 func IsTty() bool {
-	return int(C.isatty(C.int(os.Stdin.Fd()))) != 0
-}
-
-// ExecCommand executes the given command with $SHELL
-func ExecCommand(command string) *exec.Cmd {
-	shell := os.Getenv("SHELL")
-	if len(shell) == 0 {
-		shell = "sh"
-	}
-	return exec.Command(shell, "-c", command)
+	return isatty.IsTerminal(os.Stdin.Fd())
 }
diff --git a/src/util/util_unix.go b/src/util/util_unix.go
new file mode 100644
index 00000000..dcc5cb5e
--- /dev/null
+++ b/src/util/util_unix.go
@@ -0,0 +1,17 @@
+// +build !windows
+
+package util
+
+import (
+	"os"
+	"os/exec"
+)
+
+// ExecCommand executes the given command with $SHELL
+func ExecCommand(command string) *exec.Cmd {
+	shell := os.Getenv("SHELL")
+	if len(shell) == 0 {
+		shell = "sh"
+	}
+	return exec.Command(shell, "-c", command)
+}
diff --git a/src/util/util_windows.go b/src/util/util_windows.go
new file mode 100644
index 00000000..a660f39e
--- /dev/null
+++ b/src/util/util_windows.go
@@ -0,0 +1,17 @@
+// +build windows
+
+package util
+
+import (
+	"os"
+	"os/exec"
+)
+
+// ExecCommand executes the given command with $SHELL
+func ExecCommand(command string) *exec.Cmd {
+	shell := os.Getenv("SHELL")
+	if len(shell) == 0 {
+		shell = "cmd"
+	}
+	return exec.Command(shell, "/c", command)
+}