diff -r 23a892ae0220 .hgignore
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/.hgignore	Fri Oct 02 14:09:28 2009 -0700
@@ -0,0 +1,8 @@
+# This file supports two syntax types, glob and regexp.
+# In either case, the backslash is an escape and must be doubled to get a literal backslash
+
+syntax: glob
+
+# Exclude object files:
+bin.v2
+BoostBuildLog.txt
\ No newline at end of file
diff -r 23a892ae0220 libs/iostreams/src/mapped_file.cpp
--- a/libs/iostreams/src/mapped_file.cpp	Thu Oct 01 18:26:10 2009 -0700
+++ b/libs/iostreams/src/mapped_file.cpp	Fri Oct 02 14:09:28 2009 -0700
@@ -169,9 +169,9 @@
     #ifndef NDEBUG
         msg += std::string(" (\"") + impl.path_ + "\")";
     #endif
-    if (impl.mapped_handle_ != INVALID_HANDLE_VALUE)
+    if (impl.mapped_handle_ != NULL)
         ::CloseHandle(impl.mapped_handle_);
-    if (impl.handle_ != NULL)
+    if (impl.handle_ != INVALID_HANDLE_VALUE)
         ::CloseHandle(impl.handle_);
     impl.clear(true);
     throw_system_failure(msg);
@@ -399,8 +399,13 @@
     return;
 }
 
+#ifdef BOOST_IOSTREAMS_WINDOWS
+bool mapped_file_source::is_open() const
+{ return !!pimpl_ && pimpl_->handle_ != INVALID_HANDLE_VALUE; }
+#else
 bool mapped_file_source::is_open() const
 { return !!pimpl_ && pimpl_->handle_ != 0; }
+#endif
 
 int mapped_file_source::alignment()
 { return static_cast<int>(sysconf(_SC_PAGESIZE)); }