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grep awk example script

Sed and awk can be cryptic. I much prefer Perl, as I think it is easier to understand the flow.

For example, in Perl, you could do:

#!/usr/bin/perl
$ok=0;
while (<>) {
if (/MARK/) {
  $ok=1;next;
}
print if $ok;
$ok=0;
}
 

The logic is identical to the awk script below, but I think it's easier to understand if you have no knowledge of either language.

From - Fri Jun 16 07:27:48 2000
Message-ID: <3945CF25.F79F60DE@idealgroup.com> 
Date: Mon, 12 Jun 2000 23:05:25 -0700
From: Darryl Krasman <darryl@idealgroup.com>
Newsgroups: comp.unix.sco.misc
Subject: Re: Newbie grep question
References: <m131cNG-000CnpC@egps.com> 

Nachman Yaakov Ziskind wrote:
> 
> ... any easy way to sed/awk/grep out the line AFTER the marker line?
> I.e., I have text like this:
> 
> junk
> junk
> MARK
> I want this line
> junk
> junk
> junk
> MARK
> I want this line
> junk
> junk
> MARK
> I want this line
> junk
> junk
> junk
> junk
> MARK
> I want this line
> MARK
> I want this line
> 
> and so forth? No particular patterns/line counts to rely on - just the
> presence of "MARK" lets me know that the next line is valuable.  I spent some
> time reading man pages, and managed to hit
> MEGO. :-(
> 
> SCO OSE 505
> 
> Thanks!

Assuming your data is in a file called "data" try this:
$ awk '/^MARK/ { OK = 1; continue } OK == 1 { print $0; OK = 0 }' data
-- 
Darryl
Ideal Computer Group Inc.

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