Re: unique IDs for connections to ipsvd programs

* Message by -Charlie Brady- from Tue 2007-11-13:
>
> On Tue, 13 Nov 2007, Lasse Kliemann wrote:
>
>> * Message by -Charlie Brady- from Mon 2007-11-12:
>>>
>>> On Thu, 8 Nov 2007, Lasse Kliemann wrote:
>>>
>>>> That's the problem. With many concurrent connections, these outputs will
>>>> be garbled.
>>>
>>> In what sense would they be/are they garbled?
>>
>> Example:
>>
>> tcpsvd 0 2000 sh -c 'echo -n "$$: " >&2 ; uuidgen >&2'
>>
>> Now I start hammering this service with requests.
>> Here is what can happen to the output:
>>
>> 9804: b0861e71-8143-4d43-851d-6df5acc8fb44
>> 9809: c07a8d79-aa10-43fd-8104-1626e9dad863
>> 9810: 9814: fb968e73-5765-49df-8353-02ea0cd1d812
>> 3646ac5e-c147-44ca-abcb-a5a84e087c0e
>> 9818: f0312d9d-a83e-4497-b80c-4ea3537c5a6b
>
> The problem here is that you have two half lines written by different 
> processes. Don't do that, and you are much less likely to have interleaved 
> logs. Have your process write full log lines in a single write and you will 
> never see interleaved logs.
>
> What do you see if you do:
>
> tcpsvd 0 2000 sh -c 'echo "$$:" $(uuidgen) >&2'

I could not reproduce the above problem with this construct. First of all, 
thanks for the advice!

What magnitude is the probability of that I will still get interleaved logs 
with this solution? Is it like the same order of magnitude as the probability 
that, say, uuidgen will generate the same ID twice? Then it would not matter.

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