G'day Jalcock501,

You can read your input as multiline blocks: see '$/' in perlvar. Each of the individual lines in those blocks can be matched for the starting characters you want: see the 'g' and 'm' modifiers, the '^' and '$' anchors and '[...]' character classes in perlre.

With the sample input you provided, this code: 

#!/usr/bin/env perl -l

use strict;
use warnings;
use autodie;

my $re = qr{^([jEG].*)$}m;

{
    local $/ = "\nh";

    open my $fh, '<', 'pm_1055252_data.txt';

    while (<$fh>) {
        print "*** h-block #$.";
        print $1 while /$re/g;
    }

    close $fh;
}

[download]

produces this output:

*** h-block #1
j1000010017 6790194100109201301092013Test Data           N PW09-3PY248
+018BIK20
E99HEADER|004|001|
E99INSSCH|248|
E99POLCOM|3||CAP01|66|3301R7435459|||||
E99INSFAC2|MSRA01_1||||||"LNI10708"|
G3301R7435459:LNI10708                                      
*** h-block #2
j1000010017 6790194100109201301092013Test Data           M PW09-3PY248
+005BIK00
E99HEADER|004|001|
E99INSSCH|248|
E99POLCOM|3||CAP01|66|3301R7435459|||||
E99INSFAC2|MSRA01_1||||||"LNI10708"|
G3301R7435459:LNI10708                                      
*** h-block #3
j1000010017 6790194100109201301092013Test Data           L PW09-3PY248
+006BIK10
E99HEADER|004|001|
E99INSSCH|248|
E99POLCOM|3||CAP01|66|3301R7435459|||||
E99INSFAC2|MSRA01_1||||||"LNI10708"|
G3301R7435459:LNI10708

[download]

-- Ken

In reply to Re: Search file for certain lines by kcott
in thread Search file for certain lines by Jalcock501

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