Clean up.

examples/echo/main.go

@@ -6,6 +6,8 @@ import (
 	"flag"
 	"io"
 	"os"
+
+	"github.com/wetware/go/std/system"
 )
 
 //export echo
@@ -25,8 +27,16 @@ func main() {
 	}
 
 	if *serve {
-		// Signal to caller that this module is ready to handle
-		// incoming method calls.
-		os.Exit(0x00ff0000)
+		// Yield control to the scheduler.
+		os.Exit(system.StatusAwaiting)
+		// The caller will intercept interface{ExitCode() uint32} and
+		// check if e.ExitCode() == system.StatusAwaiting.
+		//
+		// The top-level command will block until the runtime context
+		// expires.
 	}
+
+	// Implicit status code 0 works as expected.
+	// Caller will resolve to err = nil.
+	// Top-level CLI command will unblock.
 }

std/system/system.go

@@ -0,0 +1,3 @@
+package system
+
+const StatusAwaiting = 0x00ff0000