Project root directory .gitignore

7, the project root directory .gitignore
  # this is a comment - Git will be ignored
  * .a # ignore all files ending .a
  # lib.a except lib.a!
  TODO files under / TODO # only ignore the root directory of the project , excluding su bdir / TODO
  build / # ignore all files in the build / directory
  doc / *. txt # ignore doc / notes.txt but excluding doc / server / arch.txt