Documentation Clarification

@agentzh

The example documentation for resty.random.bytes() contains a while loop. Is there a situation where resty.random.bytes() can return nil, or is this an error in the documentation?

    local resty_random = require "resty.random"
    local str = require "resty.string"
    local strong_random = resty_random.bytes(16,true)
        -- attempt to generate 16 bytes of
        -- cryptographically strong random data
    while strong_random == nil do
        strong_random = resty_random.bytes(16,true)
    end
    ngx.say("random: ", str.to_hex(strong_random))

Start with the resty.random.bytes() documentation example and check the function's documented return behavior for cryptographically strong output. Confirm whether nil is a possible result, then update the example or its explanation so the retry loop accurately reflects the API.