hash_init
PHP 5 >= 5.1.2, PHP 7, PHP 8, PECL hash >= 1.1
hash_init - Initialize an incremental hashing context
Manual
hash_init(
string$algo,
[int$flags = 0],
[string$key = ""],
[array$options = []] ): HashContext
Parameters
- algo
-
Name of selected hashing algorithm (i.e. "md5", "sha256", "haval160,4", etc..). For a list of supported algorithms see hash_algos.
- 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 Values
Returns a Hashing Context for use with hash_update, hash_update_stream, hash_update_file, and hash_final.
Changelog
| Version | Description |
| 8.1.0 | The options parameter has been added. |
| 7.2.0 | Usage of non-cryptographic hash functions (adler32, crc32, crc32b, fnv132, fnv1a32, fnv164, fnv1a64, joaat) with HASH_HMAC was disabled. |
| 7.2.0 | Return HashContext instead of resource. |