Initial applications isolation support using Linux namespaces.

src/nxt_capability.h

@@ -0,0 +1,17 @@
+/*
+ * Copyright (C) Igor Sysoev
+ * Copyright (C) NGINX, Inc.
+ */
+
+#ifndef _NXT_CAPABILITY_INCLUDED_
+#define _NXT_CAPABILITY_INCLUDED_
+
+typedef struct {
+    uint8_t  setid;  /* 1 bit */
+} nxt_capabilities_t;
+
+
+NXT_EXPORT nxt_int_t nxt_capability_set(nxt_task_t *task,
+    nxt_capabilities_t *cap);
+
+#endif /* _NXT_CAPABILITY_INCLUDED_ */