Re: [parisc-linux] getdents

[Grant Grundler <grundler@cup.hp.com>]

Matthew Wilcox wrote:
...
> I've done the following:
> 
> struct hpux_dirent {
> 	long	d_off_pad; /* we only have a 32-bit off_t */
> 	long	d_off;
> 	ino_t	d_ino;
> 	short	d_reclen;
> 	short	d_namlen;
> 	char	d_name[1];
> };
> 
> I think that's the right way round to put the padding for a big-endian
> machine.

Mathew,
Sorry, it doesn't look right to me.
I not sure the following is "right" either but "looks more right":

#ifdef __LP64__
	long d_off;
#else
	int d_off_pad;
	int d_off;
#endif

The problem is the offset for the d_off has to be different for
32-bit applications than it will be for 64-bit applications.
gcc has to behave the same way if we want binary compatibility.
In "wide-mode" HP-UX compiler uses 64-bit long/pointer and int
remains 32-bit.  Ergo the name "LP64".

devresource.hp.com has a "HP-UX 64-bit Porting and Transition Guide,
June 1998" in the Document library. It's an interesting reference on
HP-UX kernel interacts with 32/64-bit binaries and has some interesting
gotchas.

hope this helps,
grant

Grant Grundler
Unix Developement Lab
+1.408.447.7253