[ale] Binary Grep

[Joe Steele]

On Wednesday, November 17, 2004 1:34 PM, Fletch wrote:
> 
> $ perl -le 'print "a" x 2040, "\xff" x 16, "b" x 512' > foo
> $ perl -lne 'BEGIN{$/=\1024}$o=($.-1)*1024-length$b;$b.=$_;print "hit byte ", $o + $-[0] if $b =~ /\xff{16}/;$b=substr($b,-15,15)' foo
> hit byte 2040
>

Well, since I've already been labeled a spoil sport...  :)

What about:

$ perl -le 'print "a" x 400, "\xff" x 16, "a" x 400, "\xff" x 16, "a" x 400, "\xff" x 16' > foo
$ perl -lne 'BEGIN{$/=\1024}$o=($.-1)*1024-length$b;$b.=$_;print "hit byte ", $o + $-[0] if $b =~ /\xff{16}/;$b=substr($b,-15,15)' foo
hit byte 400
hit byte 1232
^^^^^^^^^ No hit byte at 816 :(

Trying again:
$ perl -le 'print "a" x 400, "\xff" x 16, "a" x 400, "\xff" x 16, "a" x 400, "\xff" x 16' > foo
$ perl -lne 'BEGIN{$/=\31}$o=($.-1)*31-length$b;$b.=$_;print"hit byte ",$o+$-[0]if$b=~/\xff{16}/;$b=substr($b,-15,15)' foo
hit byte 400
hit byte 816
hit byte 1232

Notice also that I have cut down on the gratuitous use of needless 
white space without any loss of readability :)

--Joe