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Comment by nieve | Hacker News Reader

Is there support for reverse lookup that I'm just overlooking? There's of PTR records being used for reverse lookups, but no sign of how to do it without reversing the octets by hand.

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I didn't think that feature fit. Would people really use a general DNS client for this? I use nslookup.

It already works in dog, so just a matter of adding an option to alleviate the manual work:

  $ dig +short -x 209.216.230.240
  news.ycombinator.com.
  $ dog PTR 240.230.216.209.in-addr.arpa.
  PTR 240.230.216.209.in-addr.arpa. 23h59m44s   "news.ycombinator.com."

And yes, I use dig -x quite often.

Does it need to be an option ? I'm accustomed to using host and it just does it by default if it is given an IP as argument.

This is my thinking too. I could add the option if there's enough interest, but aren't there already dedicated tools to do this?

As an example: I sometimes run 'curl ifconfig.me' to get my public IP from the command-line, but I wouldn't expect curl to add an '--ip' option to make this specific query easier to run. curl is a general tool, and the fact that you can use HTTP to get your public IP doesn't mean it needs a top-level option in an HTTP client. (I get that reverse lookup is an internet standard, and ifconfig.me is a third-party service, but still.)

I don't think gp is against the feature. They're saying

  dog 209.216.230.240

should directly perform a PTR lookup instead of requiring something like

  dog -x 209.216.230.240

Here's how host works when you give it an IP address as opposed to a domain name:

  $ host 209.216.230.240
  240.230.216.209.in-addr.arpa domain name pointer news.ycombinator.com.
  $ host news.ycombinator.com
  news.ycombinator.com has address 209.216.230.240

In my work I use dig -x extensively, and would love to see a similar feature in dog.

If it can see that an argument is an IP address and automatically do the PTR lookup for me, even better!

dig has got the `-x` switch that simplifies the reverse lookups.

I would +1 that I use dig for this all the time.

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