Does someone know if you can use regex to grep through a scalar value you just read out from a file in binmode?

I want to read out say 1000 bytes of a file, and then scan that 100 bytes for a string. But I do NOT want to first unpack it because I'm hoping that avoiding the unpack may save some time.

Or am I fooling myself into thinking that dealing with the scalar in binary form will be any faster than unpacking and then using normal regex?

If I do unpack, what's the best way to do that? 

open BIN_IN, "<test.elf";
binmode BIN_IN;

   read(BIN_IN, $stuff, 1000,0);
   if ($stuff =~ /7F/) {print "got it!\n";}

   @tmp = unpack("(H2)*", $stuff);
   foreach $h (@tmp) {
      print "$h ";
   }

close BIN_IN;

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Justin Eltoft

"If at all god's gaze upon us falls, its with a mischievous grin, look at him" -- Dave Matthews

In reply to Way to grep binary scalar without unpacking by Eradicatore

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