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Re: [Sheflug] quick bash question



Hi,

On 29/01/11 20:10, Christopher Brown wrote:
I know the hostname I want to lookup - e.g. mail.lug.org.uk and want
to get the PTR record in one line and the shortest number of
key-strokes as possible.

I can get the IP in one command:

host mail.lug.org.uk

and get the PTR record in another:

dig -x 217.147.93.68

but have no idea how to combine the two or pipe output from the first
to the second. I can probably get it in a single command but would be
interested in the solution anyway.

I'm sure there will be something easier, but one way at least:

  dig -x `host mail.lug.org.uk | cut -f 4 -d ' '`

That line is takeing the output from "host mail.lug.org.uk" and piping it through cut to cut out the 4th item, delimited by spaces, which happens to be the IP address. Then that is fed onto the command line for dig.

Hope it helps,
Matt

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Matt Marsh

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