silence CC warnings on >= VC 2005

unix/dcache:
- make extern.h be first for Win32 warnings disable

unix/runargv.c:
- extern.h includes signal.h, specifying signal.h before extern.h causes
  the Win32 specific defines which disable warnings to be skipped, the
  reason for signal.h before extern.h is before git history and is
  therefore unknown

win95/switchar.c:
- all 3 includes are in extern.h

extern.h

@@ -30,6 +30,19 @@
 /* For MSVC++ needs to include windows.h first to avoid problems with
  * type redefinitions. Include it also for MinGW for consistency. */
 #if defined(__MINGW32__) || defined(_MSC_VER)
+/* silence warnings about using null term strings in >= VC 2005
+sysintf.c(918) : warning C4996: 'strcat' was declared deprecated
+        Message: 'This function or variable may be unsafe. Consider using strcat
+_s instead. To disable deprecation, use _CRT_SECURE_NO_DEPRECATE. See online hel
+p for details.' */
+#define _CRT_SECURE_NO_DEPRECATE
+/* silence warnings about using POSIX name funcs in >= VC 2005
+sysintf.c(1132) : warning C4996: 'unlink' was declared deprecated
+        C:\Program Files\Microsoft Visual Studio 8\VC\INCLUDE\stdio.h(290) : see
+ declaration of 'unlink'
+        Message: 'The POSIX name for this item is deprecated. Instead, use the I
+SO C++ conformant name: _unlink. See online help for details.' */
+#define _CRT_NONSTDC_NO_DEPRECATE
 #define WIN32_LEAN_AND_MEAN
 #include <windows.h>
 #endif

unix/dcache.c

@@ -35,11 +35,11 @@
 #undef __WIN32__
 #endif
 
+#include "extern.h"
 #ifdef __APPLE__
 #include <sys/types.h>
 #endif
 #include <dirent.h>
-#include "extern.h"
 #include <sysintf.h>
 
 

unix/runargv.c

@@ -106,8 +106,6 @@ _finished_child(pid, status) [unix/runargv] handles the finished child. If
   with runargv().
 */
 
-#include <signal.h>
-
 #include "extern.h"
 
 #ifdef HAVE_WAIT_H

win95/switchar.c

@@ -23,9 +23,7 @@
 --      Use cvs log to obtain detailed change logs.
 */
 
-#include <stdlib.h>
-#include <stdio.h>
-#include "stdmacs.h"
+#include "extern.h"
 
 getswitchar()/*
 ===============