Define stdin, stdout and stderr

Makefile.dep

@@ -7,6 +7,25 @@ ifneq (,$(findstring vtimer,$(USEMODULE)))
 	endif
 endif
 
+
+ifneq (,$(findstring pnet, $(USEMODULE)))
+	ifeq (,$(findstring posix, $(USEMODULE)))
+		USEMODULE += posix
+	endif
+	ifeq (,$(findstring destiny, $(USEMODULE)))
+		USEMODULE += destiny
+	endif
+	ifeq (,$(findstring net_help, $(USEMODULE)))
+		USEMODULE += net_help
+	endif
+endif
+
+ifneq (,$(findstring posix, $(USEMODULE)))
+	ifeq (,$(findstring uart0, $(USEMODULE)))
+		USEMODULE += uart0
+	endif
+endif
+
 ifneq (,$(findstring uart0,$(USEMODULE)))
 	ifeq (,$(findstring lib,$(USEMODULE)))
 		USEMODULE += lib	
@@ -42,18 +61,6 @@ ifneq (,$(findstring at86rf231,$(USEMODULE)))
 	endif
 endif
 
-ifneq (,$(findstring pnet, $(USEMODULE)))
-	ifeq (,$(findstring posix, $(USEMODULE)))
-		USEMODULE += posix
-	endif
-	ifeq (,$(findstring destiny, $(USEMODULE)))
-		USEMODULE += destiny
-	endif
-	ifeq (,$(findstring net_help, $(USEMODULE)))
-		USEMODULE += net_help
-	endif
-endif
-
 ifneq (,$(findstring destiny,$(USEMODULE)))
 	ifeq (,$(findstring sixlowpan,$(USEMODULE)))
 		USEMODULE += sixlowpan

sys/posix/include/unistd.h

@@ -24,6 +24,10 @@
 #ifndef _UNISTD_H
 #define _UNISTD_H
 
+#define STDIN_FILENO    0   ///< stdin file descriptor
+#define STDOUT_FILENO   1   ///< stdout file descriptor
+#define STDERR_FILENO   2   ///< stderr file descriptor
+
 /**
  * @brief   Close a file descriptor.
  * @details shall deallocate the file descriptor indicated by *fildes*. To