For reasonable-sized files (ones that fit comfortably in system memory): load the file's contents into a perl scalar, say $foo. Then $fingerprint = md5($foo);

If you look through the documentation you have for it, you'll get some advice on other methods; e.g. (the object-oriented versions) :

my $file ="/file/to/hash";
my $md5 = Digest::MD5->new();

$md5->addfile($file);
$md5->add("seekrit passwerd"); # not the best choice for one, but ...

my $digest = $md5->digest;
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I got this straight out of the docs, more or less. HTH

Philosophy can be made out of anything. Or less -- Jerry A. Fodor

Small correction:

my $file = "/file/to/hash";
my $md5 = Digest::MD5->new();

open(MD5, $file) || die "Unable to open file: $!\n";
binmode(MD5);

$md5->addfile(*MD5);
$md5->add("seekrit passwerd"); # tee hee

my $digest = $md5->digest;
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Your original code will not work with the latest Digest::MD5, producing the error "Not a valid filehandle." I know this because I'm currently writing a utility script that uses MD5 to verify downloaded files (for the Slackware distrib, actually) and I tried it your way to no avail. =)

'kaboo