Split file by vector of line numbers

Question

I have a large file, about 10GB. I have a vector of line numbers which I would like to use to split the file. Ideally I would like to accomplish this using command-line utilitie

Answer 1

This might work for you:

csplit -z file 2 5

or if you want regexp:

csplit -z file /2/ /5/

With the default values, the output files will be named xxnn where nn starts at 00 and is incremented by 1.

N.B. The -z option prevents empty elided files.