(no version information, might be only in CVS)
hash_init -- Initialize an incremental hashing context
Name of selected hashing algorithm (i.e. "md5", "sha256", "haval160,4", etc..)
Optional settings for hash generation, currently supports only one option: HASH_HMAC. When specified, the key must be specified.
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.
Returns a Hashing Context resource for use with hash_update(), hash_update_stream(), hash_update_file(), and hash_final().