rem: const char *from_base; char *to; int ret;  from_base = base_name (from); to = path_concat (to_dir, from_base, NULL); ret = install_file_in_file (from, to, x);
add: const char *from_base = base_name (from); char *to = path_concat (to_dir, from_base, NULL); bool ret = install_file_in_file (from, to, x);
context: install_file_in_dir (const char *from, const char *to_dir,		     const struct cp_options *x){  const char *from_base;  char *to;  int ret;  from_base = base_name (from);  to = path_concat (to_dir, from_base, NULL);  ret = install_file_in_file (from, to, x);  free (to);  return ret;}