On Sun, Dec 21, 2008 at 2:45 PM, erik quanstrom <quans...@quanstro.net> wrote: > okay, so you're using DMAPPEND like sbrk(2). how do you avoid > clients caring about the address of this new hunk of memory?^u > clients caring about the offset of this hunk of the file? > that is, the same problem malloc has in a multi-threaded app > with sbrk.
in google's filesystem, i believe a write returns the offset it actually wrote at. if 9p was extended to do that, maybe per-fid append semantics might be more useful. (although if appending writes were rare enough, i suppose you could write the block with a unique identifier and scan to find where it actually ended up)