hash_init
Description
Syntax
hash_init(
string $algo,
int $flags = 0,
string $key = "",
array $options = []
): HashContextParameters
algo
Name of selected hashing algorithm.
flags
Optional settings for hash generation, currently supports only one option: HASH_HMAC. When specified, the key must be specified.
key
When HASH_HMAC is specified for flags, a shared secret key to be used with the HMAC hashing method must be supplied in this parameter.
options
An array of options for the various hashing algorithms. Currently, only the "seed" parameter is supported by the MurmurHash variants.
Return
Returns a Hashing Context for use with hash_update(), hash_update_stream(), hash_update_file(), and hash_final().
Examples
1 · algo
<? $algo = 'sha384'; $return = hash_init($algo); hash_update($return, 'Hello'); echo hash_final($return); ?>
3519fe5ad2c596efe3e276a6f351b8fc0b03db861782490d45f7598ebd0ab5fd5520ed102f38c4a5ec834e98668035fc
2 · flags key
<? $algo = 'sha384'; $flags = HASH_HMAC; $key = 'secret'; $return = hash_init($algo, $flags, $key); hash_update($return, 'Hello'); echo hash_final($return); ?>
0a18a877cf68b022767a7c9be11d132141ee63272d3fd3110897d3c2c86940ad9f07c758545983c09342845cf19cb4b8
3 · options · empty
<? $algo = 'sha384'; $flags = 0; $key = ''; $options = []; $return = hash_init($algo, $flags, $key, $options); hash_update($return, 'Hello'); echo hash_final($return); ?>
3519fe5ad2c596efe3e276a6f351b8fc0b03db861782490d45f7598ebd0ab5fd5520ed102f38c4a5ec834e98668035fc
4 · options · seed
<? $algo = 'murmur3f'; $flags = 0; $key = ''; $options = ['seed' => 42]; $return = hash_init($algo, $flags, $key, $options); hash_update($return, 'Hello'); echo hash_final($return); ?>
2365fb86a62c2c3ba0c2a44a316b36e2
