Equivalent to get_flag(cwd, Cwd). To set the current working directory, use set_flag(cwd, Directory) or cd(Directory).
Success:
     [eclipse]: sh(pwd).
     /home/user/test
     yes.
     [eclipse]: getcwd(Cwd).
     Cwd = "/home/user/test/"
     yes.
Fail:
    getcwd("nodirectory").
Error:
      getcwd(1).           (Error 5).
      getcwd(atom).        (Error 5).