Re: Patch to eliminate user space memory copying in 'cp'

[Jim Meyering]

"Spinka, Kristofer" <address@hidden> wrote:
>   You will have to incorporate the check for sendfile, but otherwise
> this patch should avoid the most common kernel<->user space read/write
> transitions.

Thank you for that patch.  It looks like a fine optimization.

I'll work on integrating it after coreutils-5.0.
Considering this warning in the Linux man page

       Other Unixes often implement sendfile with different semantics and
       prototypes. It should not be used in portable programs.

we'll need a stronger configure-time test.

FYI, the latest test release is here:

  ftp://alpha.gnu.org/gnu/coreutils/coreutils-4.5.11.tar.bz2
  (coreutils is the union of fileutils, textutils, and sh-utils)