Turn on random access for Syzygy files in Windows (#1840)
authormstembera <m_stembera@yahoo.com>
Sun, 23 Dec 2018 15:09:03 +0000 (07:09 -0800)
committerMarco Costalba <mcostalba@users.noreply.github.com>
Sun, 23 Dec 2018 15:09:03 +0000 (16:09 +0100)
* This is the Windows version of
https://github.com/official-stockfish/Stockfish/pull/1829

No functional change.

src/syzygy/tbprobe.cpp

index 60979a5687409a41001e93332f0019ffcae3e330..57c7d872e1b496a104774582de1a07838b4587af 100644 (file)
@@ -224,8 +224,9 @@ public:
             exit(1);
         }
 #else
+        // Note FILE_FLAG_RANDOM_ACCESS is only a hint to Windows and as such may get ignored.
         HANDLE fd = CreateFile(fname.c_str(), GENERIC_READ, FILE_SHARE_READ, nullptr,
-                               OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, nullptr);
+                               OPEN_EXISTING, FILE_FLAG_RANDOM_ACCESS, nullptr);
 
         if (fd == INVALID_HANDLE_VALUE)
             return *baseAddress = nullptr, nullptr;