Working on backing files.

Also started a sketches project to illustrate quick ideas.

File.h

@@ -25,6 +25,7 @@
 #define KEPP__FILE_H_
 
 
+#include <filesystem>
 #include <fstream>
 #include <ios>
 #include <string>
@@ -32,6 +33,12 @@
 #include "Defs.h"
 
 
+typedef std::optional<std::ofstream *> OptOutFileStream;
+typedef std::optional<std::ifstream *> OptInFileStream;
+
+
+
+/// Files default to being read/write.
 static constexpr std::ios::openmode	DefaultMode =
     std::ios::in|std::ios::out;
 
@@ -41,18 +48,41 @@ class File {
 public:
 	File(std::string fPath);
 
-	const std::string &Path() const;
+	const std::string Path();
 	void SetPath(const std::string &fPath);
 
-	// int Refresh(std::);
 
+	OptOutFileStream Flush();
+	OptInFileStream Refresh();
 
+	/// The readonly attribute on a File is a virtual write
+	/// protection, and does not reflect the permissions on
+	/// the file itself. For that, see IsWriteable.
 	[[nodiscard]] bool IsReadOnly() const { return this->readOnly; };
 	void MarkReadOnly() { this->readOnly = true; }
 	void ClearReadOnly() { this->readOnly = false; }
 
+	/// Size returns the size of the file on disk.
+	size_t			Size();
+
+	/// Exists checks whether the file exists on disk.
+	bool			Exists();
+
+	/// IsWriteable checks whether the current user has write
+	/// permissions for the file.
+	bool			IsWriteable();
+
+	/// IsReadable checks whether the current user has read
+	/// permissions on the file.
+	bool			IsReadable();
+
+	/// IsReadWriteable checks whether the current user has both
+	/// read and write permissions on the file.
+	bool			IsReadWriteable();
+
 private:
-	std::string		path;
+
+	std::filesystem::path	path;
 	bool			readOnly;
 	std::ios::openmode	mode;
 };