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What is C-spring?

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Cryptographically secure
pseudorandom number generator.

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A secure way of generating random data.

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There are random number generators in PHP,
RAN for instance.

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But none of the options in
version five are very secure.

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In PHP seven, they put together a system
interface to the operating systems

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random number generator.

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Because we can now use the operating
system's random number generator,

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if that gets hacked,
we have bigger problems.

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It probably means your entire
system is compromised, and

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there's a flaw in your
operating system itself.

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Secure random numbers are especially
useful when generating random passwords or

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password.

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What does this look like for
you as a developer?

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You now have two new functions to use,
random int and random bytes.

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When using random_bytes you
supply a single argument link,

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which is the link of the random string,
that should be returned it bytes.

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random_bytes then returns a string

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containing the requested number of
cryptographically secure random bytes.

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If we combine this with
something like bin2hex,

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we can get the hexadecimal representation.

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These are bytes, not integers.

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If you are looking to
return a random number, or

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integer, you should use
the random_int function.

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When using random_int,
you supply two arguments, min and max.

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This is the minimum and
maximum numbers you want to use.

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For example, random_int(1,20) would
return a random number between 1 and

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20, including the possibility of 1 and 20.

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Some random errors and exceptions to note.

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Min and max must be between the system
setting of PHP_INT_MIN and PHP_INT_MAX.

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If an appropriate source of
randomness cannot be found,

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an exception will be thrown.

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If invalid parameters are given,
a TypeError will be thrown.

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If max is less than min,
an Error will also be thrown.

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Although this isn't really a gotcha,
if you are using the ran function for

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anything even remotely secure, you'll want
to change that ran function to randomint.