- Tweaked build for linux.

- Tweaked how errno is sent back to Java land.

src/main/java/net/rubygrapefruit/platform/internal/FunctionResult.java

@@ -3,6 +3,10 @@ package net.rubygrapefruit.platform.internal;
 public class FunctionResult {
     int errno;
 
+    void failed(int errno) {
+        this.errno = errno;
+    }
+
     public boolean isFailed() {
         return errno != 0;
     }