Maybe a simple state machine? 

use strict;

my $in_section = 0;

foreach (<>) {
  $in_section=1, next if m{if\s+\(some\s+condition2\s+=\s+0\)}; 
  $in_section=0, next if m{^\s*end\s+if;}; # next could be omitted...h
+ere
  print if $in_section;
}

__END__
read this data 3;
read data 4;
read this data 6;

[download]
This one reads input from a list of files given by argument (@ARGV) when called as e.g. perl cond2reader.pl *.doc (or STDIN when no arguments were given). Alternatively, you can introduce an outer loop that opens all interesting files one after another (e.g. open my $fh, '<', $file or die "..."; foreach (<$fh>) { ... }
You might need to fine-tune the regular expressions a little bit.

In reply to Re: read different loops by Perlbotics
in thread read different loops by sharan

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.