Perl

Generating Repeatable Random Data for Testing/Debugging

See more PRNG Examples

Demonstrates how to use the Fortuna PRNG to generate random-looking but repeatable non-random data for the purpose of testing and debugging. Perl

use chilkat();

$success = 0;

# This example assumes the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

$success = 0;

$fortuna = chilkat::CkPrng->new();

# Normally an application would seed the PRNG with entropy from
# some real random source.  However, sometimes we want the same
# random sequence of bytes for testing and debugging purposes.
# This a reason why GetEntropy and AddEntropy are two different methods.
# An application could omit the call to GetEntropy, and instead pass
# non-random data to AddEntropy. For example:

# Seed the PRNG with non-entropy, so we get a repeatable sequence.
# Note: AddEntropy can be called any number of times.
$success = $fortuna->AddEntropy("01020304","hex");
$success = $fortuna->AddEntropy("hello world","ascii");

# Generate some random data:
$strRandHex = $fortuna->genRandom(16,"hex");
$strRandBase64 = $fortuna->genRandom(22,"base64");
$strRandBase58 = $fortuna->genRandom(32,"base58");

print "hex random bytes: " . $strRandHex . "\r\n";
print "base64 random bytes: " . $strRandBase64 . "\r\n";
print "base58 random bytes: " . $strRandBase58 . "\r\n";

# Try it again with a different object to verify that the same results are obtained:
$fortuna2 = chilkat::CkPrng->new();

$success = $fortuna2->AddEntropy("01020304","hex");
$success = $fortuna2->AddEntropy("hello world","ascii");

$strRandHex = $fortuna2->genRandom(16,"hex");
$strRandBase64 = $fortuna2->genRandom(22,"base64");
$strRandBase58 = $fortuna2->genRandom(32,"base58");

print "hex random bytes: " . $strRandHex . "\r\n";
print "base64 random bytes: " . $strRandBase64 . "\r\n";
print "base58 random bytes: " . $strRandBase58 . "\r\n";