how can I find a string in a file, print that line and the next two lines?

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On 2004-10-13, usatim wrote:
> how can I find a string in a file, print that line and the next two lines?

Why sed?

If you have GNU grep:

grep -A2 "$string" file


With awk:

awk "/$string/ {print; getline; print; getline; print; exit}"


With the shell:

while IFS= read -r line
do
case $line in
*"$string"*) printf "%s\n" "$line"
IFS= read -r line
printf "%s\n" "$line"
IFS= read -r line
printf "%s\n" "$line"
exit
;;
esac
done < file


And if you really want to use sed:

sed -n "/$string/{p;n;p;n;p;q;}" file


--
Chris F.A. Johnson                  http://cfaj.freeshell.org/shell
 ========================================
===========================
My code (if any) in this post is copyright 2004, Chris F.A. Johnson
and may be copied under the terms of the GNU General Public License

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"Chris F.A. Johnson" <cfajohnson@gmail.com> wrote in message news:<2t5lobF1smmp7U1@uni-berli
n.de>...
> On 2004-10-13, usatim wrote: 
>
>    Why sed?
>
>    If you have GNU grep:
>
> grep -A2 "$string" file
>
>
>    With awk:
>
> awk "/$string/ {print; getline; print; getline; print; exit}"
>
>
>    With the shell:
>
> while IFS= read -r line
> do
>   case $line in
>       *"$string"*) printf "%s\n" "$line"
>                    IFS= read -r line
>                    printf "%s\n" "$line"
>                    IFS= read -r line
>                    printf "%s\n" "$line"
>                    exit
>                    ;;
>   esac
> done < file
>
>
>    And if you really want to use sed:
>
> sed -n "/$string/{p;n;p;n;p;q;}" file

Thanks for the response. I was close but I did not have the brackets
and I did not have the last ;.

I know how to find a string and delete it with sed but I have no clue
about how to find string1 and if the next line is string2, delete both
lines, throughout a file. This should be the last time I bother
everyone.

Is there a good sed book I can get. I am not happy with the one I have
(O'Reilly, sed & awk).

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tillman.h.craft@usa-spaceops.com (usatim) wrote in message news:

>
> I know how to find a string and delete it with sed but I have no clue
> about how to find string1 and if the next line is string2, delete both
> lines, throughout a file. This should be the last time I bother
> everyone.
>

sed -e '
/string1/!b
$!N
/\nstring2/d
' yourfile

>
> Is there a good sed book I can get. I am not happy with the one I have
> (O'Reilly, sed & awk).
>

That's the only book or look for the sed one-liners web site where
there are good tutorials on 'sed'.

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