[PATCH] xfsdump: don't assume getdents exists

[Christoph Hellwig]

On Wed, Nov 06, 2013 at 04:36:35PM -0500, Kyle McMartin wrote:
> New Linux ports are using a standard syscall list that does not include
> deprecated syscalls where 64-bit clean alternatives exist. As a result,
> on arm64, __NR_getdents is undefined, resulting in xfsdump failing to
> build.
> 
> To avoid that, in the case where __NR_getdents is unset in unistd.h,
> avoid building the fallback path entirely, since
> __ASSUME_GETDENTS64_SYSCALL will be true, the SYS_getdents64 case will
> be the primary (and only) path used.

Seems like we could drop this mess of a file entirely and just rely
on getdents64 from glibc.  The raison d'etre of that file appears to
support 64 bit getdents before glibc really supported it, and I don't
think we'll have to support such old configurations anymore.  I'll give
it a quick spin and see how that works out.