On 16 February 2016 at 16:42, <lucio@proxima.alt.za> wrote:

Then, it would be tempting to take the

dup(fd,0); close(fd);

out to before the if(pid==0)...

the idea is to have fd (/dev/null in this case) be standard input in the new process,

so it needs to follow the pid==0 test.

the "outside" command is one that wasn't distributed (I assume it bound a separate #I interface

on /net.alt and set it up), so the code currently probably doesn't do anything useful elsewhere.

probably the file descriptor leak comes from dnresolve.c

you can cat /proc/$dnspid/fd

where dnspid is the process id one or more of the active dns processes,

to see which files are open, after the message appears.

if there are many /dev/null open, that suggests your idea was right.

i think you're right that it leaks an fd to /dev/null in that system call, so

it should instead open /dev/null separately and assign fd before the call and close it afterwards.

even so, i wonder if that's really what's happening in every case of "more than N fds", because

the call to outside is only needed in the case that the udp under /net.alt is being

used and an open there has failed. still, looking at the /proc/N/fd file should help decide that.