The first is trivial: set the number to be the total number of context lines you want, including the matched pattern line.

The second is a little trickier: 

perl -ne 'print if $.=/pattern/?1:2..10'

[download]
In this case, it will print 10 lines after the match.

Update: so tricky, in fact, that you can't do it with the range operator. So there's no point in using $.. So you just do 

perl -ne 'print if$c=/pattern/?11:$c&&$c-1'

[download]
or any of the other solutions here. Sigh.
One that doesn't require you to add one to the number you put in: 
perl -ne 'print if(/pattern/?$c=10:$c--)>0'

[download]
Caution: Contents may have been coded under pressure.

In reply to Re^3: grep -A10 oneliner? by Roy Johnson
in thread grep -A10 oneliner? by piroufreek

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