io/FileDescriptor: add method SetBinaryMode()

src/io/FileDescriptor.cxx

@@ -172,7 +172,15 @@ FileDescriptor::CreatePipe(FileDescriptor &r, FileDescriptor &w) noexcept
 #endif
 }
 
-#ifndef _WIN32
+#ifdef _WIN32
+
+void
+FileDescriptor::SetBinaryMode() noexcept
+{
+	_setmode(fd, _O_BINARY);
+}
+
+#else // !_WIN32
 
 bool
 FileDescriptor::CreatePipeNonBlock(FileDescriptor &r,

src/io/FileDescriptor.hxx

@@ -148,10 +148,13 @@ public:
 #ifdef _WIN32
 	void EnableCloseOnExec() noexcept {}
 	void DisableCloseOnExec() noexcept {}
+	void SetBinaryMode() noexcept;
 #else
 	static bool CreatePipeNonBlock(FileDescriptor &r,
 				       FileDescriptor &w) noexcept;
 
+	void SetBinaryMode() noexcept {}
+
 	/**
 	 * Enable non-blocking mode on this file descriptor.
 	 */