Christian Franke wrote:
Both O_DIRECT and F_NOCACHE are not part of POSIX, so there probably is no portable way without at least one more nasty #ifdef.
Yes, but O_DIRECT seems to be the "de facto standard" among unices, while F_NOCACHE is only used by Apple.
POSIX provides only O_SYNC, I don't know whether this has any effect on raw devices.
Ddrescue uses O_DIRECT only for the input file, so I think O_SYNC has no effect on it.
Interestingly, F_NOCACHE does also not appear in GNU dd (coreutils 6.9). Hmm...
What makes me think if I should contribute to spread the use of F_NOCACHE in detriment of the much more widely used O_DIRECT. I think it would be better that Apple implements O_DIRECT in Darwin, but I don't know what are the chances of this happening.
An alternative patch is attached. It does not require DARWIN defined, but relies on O_DIRECT undefined or defined as 0 in Darwin's includes.
Thanks for this excellent patch. I suppose that if some future Darwin's headers define O_DIRECT it means that Darwin supports O_DIRECT, so your patch should also work in such a future Darwin version. :)
BTW: On Cygwin, 1.6-pre2 builds OOTB and works.
Thanks for the feedback. Perhaps you would like to know that 1.6-pre3 is already released. ;)
Best regards, Antonio. _______________________________________________ Bug-ddrescue mailing list [email protected] http://lists.gnu.org/mailman/listinfo/bug-ddrescue
