Re: A micro-optimisation for walkdir()

On 2020-Sep-04, Thomas Munro wrote:

> @@ -10,6 +10,7 @@ struct dirent
>  {
>       long            d_ino;
>       unsigned short d_reclen;
> +     unsigned char d_type;
>       unsigned short d_namlen;
>       char            d_name[MAX_PATH];
>  };
> @@ -20,4 +21,26 @@ DIR                   *opendir(const char *);
>  struct dirent *readdir(DIR *);
>  int                  closedir(DIR *);
> 
> +/* File types for 'd_type'. */
> +enum
> +  {
> +     DT_UNKNOWN = 0,
> +# define DT_UNKNOWN          DT_UNKNOWN

Uhm ... what do these #defines do?  They look a bit funny.

Would it make sense to give this enum a name, and then use that name in
struct dirent's definition, instead of unsigned char?