I (finally) strace'd my lsh to find out why lsh isn't appending
keys to the file. It appears to be the same problem that Eric
mentions:
open("/home/thayne/.lsh/captured_keys", O_WRONLY|O_APPEND|O_CREAT, 0600)
= 5
fcntl(5, F_SETFL, O_RDONLY|O_NONBLOCK) = 0
fcntl(5, F_SETFD, FD_CLOEXEC) = 0
<more stuff>
write(5, "\n; ACL for host foo.northsky"..., 500) = 500
poll([{fd=7, events=POLLIN|POLLRDNORM}, {fd=5, events=POLLOUT,
revents=POLLOUT}], 2, 100) = 1
write(5, "GBzUjTkW4VvQBz0feHbh4LERHVvVmVOF"..., 241) = 241
<more stuff>
And there is no close(5) - Same as what Eric mentions.
seems strange that F_SETFL is trying to set O_RDONLY . . .
I also notice that in io.c there are io_set_nonblocking() and
io_set_close_on_exec which uses F_SETFL and F_SETFD (respectively)
without prior doing a F_GETFL and F_GETFD, or'ing the bits with
the O_NONBLOCK and FD_CLOEXEC, and then using F_SETFL and F_SETFD
respectively.
seems strange again . . .
What do I know, I'm not a real programmer - I just play one on TV . . .
"Eric J. Schwertfeger" wrote:
>
> On Fri, 7 Jan 2000, Thayne Harbaugh wrote:
>
> > "Eric J. Schwertfeger" wrote:
> > >
> > > On 7 Jan 2000, Niels M�ller wrote:
> > >
> > > > Copying keys from captured_keys to known_hosts should work.
> > >
> > > It didn't, I'll look into that more this lunch, and maybe this weekend.
> > >
> >
> > Make sure you don't have an extra line of garbage on the end of your
> > captured key - similar to my problem. No, I haven't spent the moment
> > to further investigate my problem.
>
> That was the problem. I deleted the file, ran lsh, and had no garbage in
> the file. Ran lsh again, and still no garbage. Replaced captured_keys with
> 100 lines of "testing\n", this time got garbage at the end of the line.
>
> Looked at the truss output:
>
> syscall open("/home/ejs/.lsh/captured_keys",521,0600)
>
> 521 is O_APPEND|O_CREAT|O_WRONLY so that looks right.
>
> syscall fcntl(0x6,0x4,0x4)
>
> 0x4 is F_SETFL
>
> syscall fcntl(0x6,0x2,0x1)
>
> 0x2 is F_SETFD
>
> syscall write(6,0x808540c,500)
>
> syscall write(6,0x8085600,213)
>
> And we never close the file? the F_SETFD is setting close_on_exec though.
>
> I've never played with fcntl, but somehow lsh is getting the OS to ignore
> the O_APPEND flag.
