On Thu, 2007-08-30 at 00:49 +0200, Michael Holzt wrote:
> > or even
> > 10 + 1 + 16 + 1 + 39 + 1 + 5 + 1 + 39 + 1 + 5 = 119 characters
>
> Better encode it binary. E.g. for IPv4:
And better get the number of bits correct. An IP address is a 32 bit
integer, not 15 characters. Although perl converts scalars on-demand,
it correctly preserves integer values.
>
> my $id = pack("NCNNNN",$$,$start,$lip,$lport,$rip,$rport)
I thought port numbers had been pretty much refuted already.
If not, it would help to add a requirement to the list and explain why
they provide the best solution.
>
> Sum: 21 Bytes. Encoded in Base64: 28 Bytes.
For discussion, I started using sprintf("0#x%- ... ") since I expect my
logs to be text and this looks like a UUID. The number of bits is just
4* the number of characters. It is simple enough to switch to pack or
base64 later or use pack as an option for those who want binary logs.
So far no-one has come up with much objection to
sprintf("%08x-%08x-%04x",gettimeofday,$$)
This satisfies requirements (1) and (4) and Matt says it works for him.
If we need a 16-bit, RCPT counter, req (2), then:
sprintf("%08x-%08x-%04x-%04x",gettimeofday,$$,$RCPT)
If we need a host ID, req (3), then using IP-Addr (IPv4 only):
sprintf("%0x8-%0x8-%04x-%04x-%08x",gettimeofday,$$,$RCPT,$IP)
though I think a substring of config('me') might do the job and would be
IPv-agnostic. At this point we are at 128 bits (8 bytes) - same as
UUID.
--
--gh
