using sed to get the xth, yth, and zth line of a text file

I know you can use sed to get the nth line of a text file as follows:

sed -n '30p'开发者_如何学Go foo.txt

will output the 30th line of foo.txt

However, suppose I'm interested in the 30th, 39th, 43rd lines of foo.txt? Is there a way to string this together in sed?

Thanks.

Sure is...

sed -n '30p;39p;43p' foo.txt

If they are in a contiguous range, say 39-42 you can do something like this:

sed -n '39,42p' foo.txt