Moody wrote:

"What you _would_ want for this would be the ability to walk from the existing fd, however the limits of 9p walk make this a bit impossible to implement in a great way in my opinion. "

Maybe the chan could keep two fids: the original walked fid, and an opened clone of that fid? The open one could be used for read/write, etc, and the original could be used for subsequent walks.

Ron Minnich wrote:

"The question I had was, can I get the benefit of *at without doing what linux is doing, namely, for all system calls with a path, make an '...at' version.

I am guessing so, though I'm not sure it's as efficient."

Could you do something like

open ("/fd/5/as-dir/a/b/c", ...)

open ("#d/5/as-dir/a/b/c", ...)

where 5 is the file descriptor of an open directory, and "as-dir" is effectively bound to the directory it has open?

The Linux docs make passing reference to "tricks involving /proc/../fd" which seems like a better idea than adding all those *at system calls...

... from the department of partly-baked ideas...