You could maintain a small shift buffer with the last two lines read, which would work even when the data file is large. 
use strict;

my $value = 0;
my @linebuf;
open IN, "data.file" or die "$!";
for (0..1) {
   $_ = <IN>;
   push @linebuf,$_;
}
while (<IN>) {
   if (/^--/ and $linebuf[0] =~ /ABC SET/) {
     print "Matched ",$linebuf[0];
     $value++;
   }
   shift @linebuf;
   push @linebuf,$_;
}
close IN or warn "$!";
print "total found is $value\n";

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In reply to Re: Help With Parsing a File by tall_man
in thread Help With Parsing a File by PrimeLord

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