net: dial only connects to IPv4 addresses

[gopherbot]

by bortzmeyer:

What steps will reproduce the problem?
1. 8g dial.go
2. 8l -o dial dial.8
3. ./dial whois.nic.fr 43 

What is the expected output?

Connection with whois.nic.fr:43 ([2001:660:3003:2::4:24]:43) OK

What do you see instead?

Connection with whois.nic.fr:43 (192.134.4.25:43) OK

Which compiler are you using (5g, 6g, 8g, gccgo)?

8g

Which operating system are you using?

Debian "squeeze"

Which revision are you using?  (hg identify)

46c566a29e1f tip

Please provide any additional information below.

I was expecting an IPv6 connection, like with telnet:

% telnet whois.nic.fr 43
Trying 2001:660:3003:2::4:24...
Connected to whois.nic.fr.
Escape character is '^]'.
...


Isn't it the fault of LookupHost in dnsclient.go, which only queries A records?

Attachments:

1. dial.go (724 bytes)

[rsc]

Comment 1:

Yes, this is one of many such bugs in the package.
The long term plan is to change package net to use
the C library instead of doing so much itself, and
that will address concerns like this one.
Not going to touch the current code until that change
is made.

Owner changed to r...@golang.org.

Status changed to Accepted.

[rsc]

Comment 2:

Yes, this is one of many such bugs in the package.
The long term plan is to change package net to use
the C library instead of doing so much itself, and
that will address concerns like this one.
Not going to touch the current code until that change
is made.

[gopherbot]

Comment 3 by bortzmeyer:

OK. This is a pity since it will mean importing C issues (such as
memory management) but I cannot think of a better solution.
Reimplementing everything that getaddrinfo do and keeping it in synch
with the future evolutions of the libc (DNSSEC, for instance), is not
reasonable.

[rsc]

Comment 5:

$ 6.out whois.nic.fr 43
Connection with whois.nic.fr:43 ([2001:660:3003:2::4:24]:43) OK
$ 
fixed during conversion of net to use cgo

Status changed to Fixed.