Re: index-pack died on pread

From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Jul 27, 2007, 05:36 UTC
Message-ID: <alpine.LFD.0.999.0707262231280.3442@woody.linux-foundation.org>
In-Reply-To: <7vps2e5x4y.fsf@assigned-by-dhcp.cox.net>

On Thu, 26 Jul 2007, Junio C Hamano wrote:

> 
> If you mean the offset associated with fd, we actually do.

Ahh, for some reason I thought we didn't (probably because the user likely doesn't care at all), but right you are..

Show 6 quoted lines

> The original HP-UX error is confusing, as we ask pread() to
> transfer 428 bytes and it returns 0 (not returning -1 with
> EINTR).  Return value of zero is understandable, if the starting
> position is at or after the EOF, but the offset is 123601 and
> 56k objects packed from git.git repository should be longer than
> that, so that also sounds implausible.

Yeah. It is suspicious.

If somebody could run git under gdb on HP-UX (preferably compiled statically), and just disassemble the pread() thing, it would be interesting.

PA-RISC assembly is *almost* entirely unreadable, but it might show whether hpux-11.11 actually has a pread() system call or whether it is doing the "emulate with lseek" and maybe obviously buggily at that..

It really isn't that complex a system call. So I'm surprised at bugs there, and that makes me worry that there is something in git that triggers this.

		Linus