Re: Bug in Guile's Posix Networking

[Noah Lavine <noah.b.lavine@gmail.com>]

Hi all,

I think I have isolated the error (although in fact there are two
things that should be fixed).

I gdb'd Guile's executable and looked at the struct sockaddr just
before it was passed to bind. There were two mistakes.

First of all, that struct has an sa_len field which is supposed to
contain its length, but in fact contained junk. Second of all, it
should have been padded with 8 bytes of zeros at the end, but it
wasn't. After experimenting a bit, it turns out that padding with
zeros was what made the difference, but probably the sa_len field
should be fixed anyway. I'll work on a patch for this.

Noah

On Sat, Feb 12, 2011 at 8:22 PM, Noah Lavine <noah.b.lavine@gmail.com> wrote:
> Hi,
>
>> #x49 is 73 :)
>
> If I knew a facepalm emoticon, I would use it now. :)
>
>> Could the lseek could be the problem?
>
> Maybe, but I suspect not. My man page for lseek says that lseek will
> fail with ESPIPE if it is called on a socket, and my errno.h defines
> ESPIPE to be 29, which is the error we got. So that's what's happening
> there.
>
> However, I looked to see where the lseek call was coming from, and it
> happens in scm_fdes_to_port, on line 564 of fports.c. The lseek is
> done for the purpose of checking whether the port supports lseek, and
> when it returns -1, we put an entry into some data structure (port
> table?) saying that it doesn't support random access. So it looks like
> that error is actually expected in the port code.
>
> Noah
>