Use O_NOATIME while scanning (if available) to avoid updating file access times.

src/core/file_unix.cpp

@@ -133,7 +133,7 @@ void cFile::Open( const TSTRING& sFileNameC, uint32 flags )
         Close();
     
     //
-    // set up the sopen permissions
+    // set up the open permissions
     //
     int perm = 0;
 
@@ -173,6 +173,11 @@ void cFile::Open( const TSTRING& sFileNameC, uint32 flags )
         perm |= O_NONBLOCK;
 #endif
 
+#ifdef O_NOATIME
+    if (flags & OPEN_SCANNING)
+        perm |= O_NOATIME;
+#endif
+
 #ifdef O_DIRECT
     //Only use O_DIRECT for scanning, since cfg/policy/report reads
     // don't happen w/ a nice round block size.