Fork of Cscope version 15.9, with various improvements, because cscope is good and shall not be forgotten. While the original's mainentence seems abandoned and as far as I can tell you need a PhD in autoconf to compile the latest version, Csope is alive and well.
Csope shines at exploring stranger and obsecure code bases due to its TUI. It sometimes gets mislabeled as a code navigation tool, but the original documentation describes it best as a "code browsing tool". Many tools can jump you to a definition or grep for patterns, but Csope is unqie in that it allows for those and many other functionalities while providing you with a very comprehansible list of all results, ready to fire up your editor at just the spot. An example of its excelence is this project. The Cscope codebase used to be a total mess, fixing it would have been a lost cause, if not for Cscope itself. Well, Csope now.
The readline integratoin should be complete -please let us know if not-, except for your prompt being used, which could easily break the TUIs display.