On 08/01/2016 02:52 PM, Rodolfo Medina wrote:
> with the following simple script:
>
> #!/bin/sh
>
> cat index.idx | sort > index.ind
>
> I sort the contents of a file and write it in another file. Now, I want that
> a
> small vertical space, i.e. an empty line or two, were inserted before all the
> words that start with a new letter.
If the first letters of your words are only ASCII characters
(or you are using an 8 bit character encoding), then the
following should do the trick:
sort < index.idx | awk 'BEGIN {
c = -1;
}
{
if (substr($0, 1, 1) != c && c != -1)
printf("\n\n");
c = substr($0, 1, 1);
print;
}' > index.ind
See also:
https://en.wikibooks.org/wiki/AWK
Regards,
Christian
