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showascii

by photon (Novice)
on Jul 20, 2003 at 03:37 UTC ( [id://275985]=CUFP: print w/replies, xml ) Need Help??

- dumps ascii values of all characters matching \W - reads from file or stdin).. - useful for analyzing unkown binary file formats.. - files must fit into ram 
#!/usr/bin/perl

$filename = $ARGV[0] || '/dev/stdin';

$/=undef;
open(FILE,$filename) or die $!;
$file=<FILE>;
close(FILE);
$file=~s/(\W)/&replace($1)/eg;
print $file;

sub replace { return "(".ord($_[0]).")" }

[download]

Replies are listed 'Best First'.
(jeffa) Re: showascii
by jeffa (Bishop) on Jul 20, 2003 at 13:56 UTC

    If you are going to slurp an entire filehandle into memory, then do it like this: 

    my $text = do {local $/;<FILE>};

    [download]
    More consise, but also safer in that the undefining of $/ has been tucked away in a 'temporary' scope. But there is no reason to slurp the entire file into memory - you could have just as easily used a while loop to read one line at a time. In fact: 
    perl -pe 's/(\W)/"(".ord($1).")"/eg' foo.bin

    [download]
    works just as well and is more justified for not using strict. ;)

    jeffa

    L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)
[reply]
[d/l]
[select]

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