cscope 15.9-1 (amd64 binary) in ubuntu focal

 Cscope is an interactive text screen based source browsing tool.
 Although it is primarily designed to search C code (including lex
 and yacc files), it can also be used for C++ code.
 .
 Using cscope, you can easily search for where symbols are used and
 defined. Cscope is designed to answer questions like:
 .
  - Where is this variable used?
  - What is the value of this preprocessor symbol?
  - Where is this function in the source files?
  - What functions call this function?
  - What functions are called by this function?
  - Where does the message "out of space" come from?
  - Where is this source file in the directory structure?
  - What files include this header file?