hash_init
Initialize an incremental hashing context
Description
resource hash_init
( string $algo
[, int $options = 0
[, string $key = NULL
]] )
Parameters
-
algo
-
Name of selected hashing algorithm (i.e. "md5", "sha256", "haval160,4", etc..). For a list of supported algorithms see hash_algos.
-
options
-
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 options,
a shared secret key to be used with the HMAC hashing method must be supplied in this
parameter.
Return Values
Returns a Hashing Context resource for use with hash_update,
hash_update_stream, hash_update_file,
and hash_final.
Examples
Example #1 Incremental hashing example
<?php
$ctx = hash_init('md5');
hash_update($ctx, 'The quick brown fox ');
hash_update($ctx, 'jumped over the lazy dog.');
echo hash_final($ctx);
?>
The above example will output:
5c6ffbdd40d9556b73a21e63c3e0e904
See Also
- hash
- hash_algos
- hash_file
- hash_hmac
- hash_hmac_file