CString is:module

GHC C strings definitions (previously in GHC.Base). Use GHC.Exts from the base package instead of importing this module directly.
MutByteArray representing null terminated c strings. All APIs in this module are unsafe and caution must be used when using them. Completely experimental. Everything is subject to change without notice.
An exactprintable structure for docstrings
A ParamSpec derived structure that contains the meta data for string properties.