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openssl_random_pseudo_bytes

openssl_random_pseudo_bytes

Generate a pseudo-random string of bytes

string **openssl_random_pseudo_bytes** int $length bool $strong_result

Generates a of pseudo-random bytes, with the number of bytes determined by the parameter. string``length

It also indicates if a cryptographically strong algorithm was used to produce the pseudo-random bytes, and does this via the optional parameter. It's rare for this to be false, but some systems may be broken or old. strong_result

length The length of the desired string of bytes. Must be a positive integer less than or equal to . PHP will try to cast this parameter to a non-null integer to use it. 2147483647

strong_result If passed into the function, this will hold a value that determines if the algorithm used was "cryptographically strong", e.g., safe for usage with GPG, passwords, etc. true if it did, otherwise false bool

Returns the generated string of bytes.

throws an 

on failure. openssl_random_pseudo_bytes``Exception

Voorbeeld: example

<?php
for ($i = 1; $i <= 4; $i++) {
    $bytes = openssl_random_pseudo_bytes($i, $cstrong);
    $hex   = bin2hex($bytes);

    echo "Lengths: Bytes: $i and Hex: " . strlen($hex) . PHP_EOL;
    var_dump($hex);
    var_dump($cstrong);
    echo PHP_EOL;
}
?>
Lengths: Bytes: 1 and Hex: 2
string(2) "42"
bool(true)

Lengths: Bytes: 2 and Hex: 4
string(4) "dc6e"
bool(true)

Lengths: Bytes: 3 and Hex: 6
string(6) "288591"
bool(true)

Lengths: Bytes: 4 and Hex: 8
string(8) "ab86d144"
bool(true)

random_bytes``bin2hex``crypt``random_int