Good day Monks,

I'm having some difficulty searching binary data with regular expressions. The problem appears to be due to a numerical 10 within my data that is being interpreted as a line feed.

Is there any way to indicate to the regex to ignore line feeds (similar to using $\=undef for files) or any other suggestions on how to get the desired results?


The following code demonstrates the problem. Whenever I am looking for "any characters" using .{x} and the span includes a 10, it will fail to find it.

my $data = "\x04\x05\x06\x07\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f\x10\x11";

my @find = (
  # These Work
  "\x04\x05\x06\x07\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f\x10\x11",
  "\x04\x05.{4}\x0a\x0b\x0c\x0d\x0e\x0f\x10\x11",
  "\x04\x05\x06\x07\x08.{1}\x0a\x0b\x0c\x0d\x0e\x0f\x10\x11",
  "\x04\x05\x06\x07\x08\x09\x0a.{1}\x0c\x0d\x0e\x0f\x10\x11",

  #These don't work
  "\x04\x05.{5}\x0b\x0c\x0d\x0e\x0f\x10\x11",
  "\x04\x05\x06\x07\x08\x09.{1}\x0b\x0c\x0d\x0e\x0f\x10\x11"
);

foreach (@find) {
  if ($data =~ /$_/) { print "found\n" } else { print "not found\n" } 
+;
};

[download]
Running the code will output:
found
found
found
found
not found
not found


Also, does anyone know a good online regexp reference? I had an excellent reference at http://japhy.perlmonk.org/book/ bookmarked, but it looks like it has been removed.

Thanks

In reply to Using regexp with binary data by Anonymous Monk

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