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diff --git a/examples/vrfy.sig b/examples/vrfy.sig
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+#!/usr/local/lua52/bin/lua
+--
+-- Example public-key signature verification.
+--
+
+local keytype, hash = ...
+
+local openssl = require"openssl"
+local pkey = require"openssl.pkey"
+local digest = require"openssl.digest"
+
+-- generate a public/private key pair
+local function genkey(type)
+	type = string.upper(type or (not openssl.NO_EC and "EC") or "RSA")
+
+	if type == "RSA" then
+		return pkey.new{ type = "RSA", bits = 1024 }
+	elseif type == "DSA" then
+		return pkey.new{ type = "DSA", bits = 1024 }
+	else
+		return pkey.new{ type = "EC", curve = "prime192v1" }
+	end
+end
+
+local key = genkey(keytype)
+if hash == nil then
+	hash = key:getDefaultDigestName()
+end
+
+-- digest our message using an appropriate digest
+local data = digest.new(hash)
+data:update(... or "hello world")
+
+-- generate a signature for our data
+local sig = key:sign(data)
+
+-- to prove verification works, instantiate a new object holding just
+-- the public key
+local pub = pkey.new(key:toPEM"public")
+
+-- a utility routine to output our signature
+local function tohex(b)
+	local x = ""
+	for i = 1, #b do
+		x = x .. string.format("%.2x", string.byte(b, i))
+	end
+	return x
+end
+
+print("verified", pub:verify(sig, data))
+print("key-type", pub:type())
+print("hash-type", hash)
+print("signature", tohex(sig))