+/**
+ A special return value of many wxWidgets classes to indicate that
+ an invalid offset was given.
+*/
+const int wxInvalidOffset = -1;
+
+/**
+ The type used to store and provide byte offsets or byte sizes for files or streams.
+
+ It is type-defined as @c off_t on POSIX platforms
+ (see http://www.gnu.org/software/libc/manual/html_node/File-Position-Primitive.html)
+ or to @c wxLongLong_t on Windows when @c wxHAS_HUGE_FILES is defined.
+*/
+typedef off_t wxFileOffset;
+