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Need a program that read a file line by line and prints out lines 1, 2 & 3 after an empty line...

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Top Forums Shell Programming and Scripting Need a program that read a file line by line and prints out lines 1, 2 & 3 after an empty line...
# 8  
Old 06-27-2014
Quote:
Originally Posted by Ferocci
Hello gandolf989,

Tried your command with no luck at all, maybe I am doing something wrong:

Code:
$ egrep -A3 "^$" 20140624-swerrs| grep -v "^$"

It's looking for empty lines to match (and then discard), but your input actually has a space.

Try:
Code:
grep -A3  "^ $" 20140624-swerrs| grep -v "^ $"

EDIT: Actually,
Code:
grep -A3 --no-group-separator "^ $" 20140624-swerrs

depending whether you prefer dashes or blank(ish) lines as record separators.
Last edited by CarloM; 06-27-2014 at 06:59 PM..
# 9  
Old 06-28-2014
Also try

Print n number of records after blank lines, change variable n according to your need

Code:
$ awk 'c && c--; !NF{c=n}' n='3'  file

---------- Post updated at 04:26 PM ---------- Previous update was at 04:07 PM ----------

if you need blank line as well use this, we can leave next here

Code:
$ awk 'c && c--; !NF{c=n;print}' n='3'  file
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