On Wed, Jun 02, 2021 at 08:11:50PM +0000, Eric Wong wrote:
> Jeff King <peff@xxxxxxxx> wrote:
> > And so when he gets this error:
> >
> > fatal: fsync error on '.git/objects/pack/tmp_pack_NkPgqN': Interrupted system call
> >
> > presumably we were in fsync() when the signal arrived, and unlike most
> > other platforms, the call needs to be restarted manually (even though we
> > set up the signal with SA_RESTART). I'm not sure if this violates POSIX
> > or not (I couldn't find a definitive answer to the set of interruptible
> > functions in the standard). But either way, the workaround is probably
> > something like:
>
> "man 3posix fsync" says EINTR is allowed ("manpages-posix-dev"
> package in Debian non-free).
Ah, thanks. Linux's fsync(3) doesn't mention it, and nor does it appear
in the discussion of interruptible calls in signals(7). So I was looking
for a POSIX equivalent of that signals manpage but couldn't find one. :)
> > #ifdef FSYNC_NEEDS_RESTART
>
> The wrapper should apply to all platforms. NFS (and presumably
> other network FSes) can be mounted with interrupts enabled.
I don't mind that, as the wrapper is pretty low-cost (and one less
Makefile knob is nice). If it's widespread, though, I find it curious
that nobody has run into it before now.
-Peff
