This is the mail archive of the
gdb-patches@sourceware.org
mailing list for the GDB project.
Re: [PATCH] Append to input history file instead of overwriting it
- From: Eli Zaretskii <eliz at gnu dot org>
- To: Patrick Palka <patrick at parcs dot ath dot cx>
- Cc: gdb-patches at sourceware dot org
- Date: Sat, 10 Jan 2015 18:41:28 +0200
- Subject: Re: [PATCH] Append to input history file instead of overwriting it
- Authentication-results: sourceware.org; auth=none
- References: <CA+C-WL8uggYL3evJ6i78A6ySnfH-kGNaLb_a0-_3yLRm_2Si6g at mail dot gmail dot com> <1420903108-24831-1-git-send-email-patrick at parcs dot ath dot cx> <83wq4u63wu dot fsf at gnu dot org> <CA+C-WL88pk1tnTHp1FS_LMhNXiypmWify75d2eJW4w+2aLjRTA at mail dot gmail dot com> <83twzy62t5 dot fsf at gnu dot org> <CA+C-WL-E-vAXHCik8jLk9A-4E40tLLagkiNfo7nCPsbsU07gcQ at mail dot gmail dot com>
- Reply-to: Eli Zaretskii <eliz at gnu dot org>
> From: Patrick Palka <patrick@parcs.ath.cx>
> Date: Sat, 10 Jan 2015 11:17:56 -0500
> Cc: gdb-patches@sourceware.org
>
> On Sat, Jan 10, 2015 at 11:03 AM, Eli Zaretskii <eliz@gnu.org> wrote:
> >> From: Patrick Palka <patrick@parcs.ath.cx>
> >> Date: Sat, 10 Jan 2015 10:48:03 -0500
> >> Cc: gdb-patches@sourceware.org
> >>
> >> > On Windows, a call to 'rename' fails if the destination already
> >> > exists. Does the logic here cope with that?
> >>
> >> Hmm, the logic does not really cope with Windows' behavior here,
> >> because the above warning should only get emitted for unexpected
> >> failures. So I suppose we should only emit the above warning if errno
> >> != EBUSY (perhaps only on Windows systems)?
> >
> > Why EBUSY?
>
> Just a wild guess. What would be the correct error code to check for?
> Looks like it would be EACCES..
According to my testing, it's EEXIST.
> > We could also explicitly remove the target before the rename call (and
> > ignore any errors from that), which will make it work like on Posix
> > systems.
>
> I don't think that would be sufficient. In a hypothetical but
> plausible scenario, process GDB1 would call unlink(), process GDB2
> would then call unlink(), process GDB1 would then call rename()
> successfully, process GDB2 would then call rename() and fail on
> Windows despite calling unlink() on the destination.
What would you suggest that GDB2 does instead? I see no solution here
that would not fail in some way. Do you?