No need to slurp the whole thing. Just set $/ to whatever you want to look for and see if it chomps. 
my $fi = "foo\xd9bar\xd9baz\xd9nothing";
open IN, '<', \$fi or die "Die fi!\n";
$/ = "\xd9";
while (<IN>) {
  print chomp() ? "Found after $_\n" : "Not after $_\n";
}

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In reply to Re^2: how to search binary file by Roy Johnson
in thread how to search binary file by redss

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