One of my favorite ways to print out only the lines of data between delimiters is with the range operator (..) also called the "flip-flop" op. If we drop the initial print (Items found under [moo]), this can be done with a fairly straight forward one-liner: 
perl -ne'print if /^\[moo\]/../^\[cow\]/ and !/^\[/' log.log

[download]
But let's go ahead and blow this up: 
use strict;
use warnings;

open FH, '<', 'log.log' or die "can't open file\n";
print "Items found under [moo]\n";
while (<FH>) {
   if (/^\[moo\]/../^\[cow\]/) {
      print unless /^\[/;
   }
}

[download]
Basically, the left hand side of the .. op is the delimiter you want to start printing when found, and the right hand side of the .. op is the delimiter you want to stop printing when found. Since you don't want to print the delimiters themselves, you have to add a condition to do so. I picked anything that starts with a left bracket, you will have to pick something better if your data will start with one.

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

In reply to Re: print data between two regular expressions by jeffa
in thread print data between two regular expressions by Anonymous Monk

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