mt_srand — Seed the better random number generator
Description
voidmt_srand
([ int$seed
] )
Seeds the random number generator with
seed
or with a random value
if no seed
is given.
Note: As of PHP 4.2.0, there is no need
to seed the random number generator with srand() or
mt_srand() as this is now done automatically.
Parameters
seed
An optional seed value
ChangeLog
Version
Description
Since 4.2.0
The seed
becomes optional
and defaults to a random value if omitted.
Since 5.2.1
The Mersenne Twister implementation in PHP now uses a new seeding
algorithm by Richard Wagner. Identical seeds no longer produce the same
sequence of values they did in previous versions. This behavior is not
expected to change again, but it is considered unsafe to rely upon it
nonetheless.