Re: [Xenomai-core] xeno-test manpage patch

[Romain Lenglet <rlenglet@domain.hid>]

Thomas Lockhart:
> >>I wanted a compact rep.
> >>is there a std format that doesnt have a space ?
> >>its nicer for us xterm double-click cut-pasters.
> >
> > Replace the space with a "T": this is still an ISO 8601
> > format.
>
> Just a detail: it is "ISO 9601" and (fwiw) I can confirm that
> the "T" is defined there.

I am adding some more noise... ;-)

No, it is ISO 8601. There is no ISO 9601 standard (the 9000 
series is about management / quality).
http://www.iso.org/iso/en/CatalogueDetailPage.CatalogueDetail?CSNUMBER=40874&ICS1=1&ICS2=140&ICS3=30

The interesting thing about IETF's RFC 3339 is that they have 
summarized ISO 8601's syntax in ABNF, and defined a 
non-ambiguous subset of it.
The "T" is optional in ISO 8601, but they have made it mandatory 
in RFC 3339's subset to avoid ambiguity:
"ISO 8601 states that the "T" may be omitted under some 
circumstances.  This grammar requires the "T" to avoid 
ambiguity.
[...]
iso-date-time     = date "T" time"


My mistake is, I initially thought that RFC 3339 recommended a 
space instead of "T", but this is only an option for 
readability:
"NOTE: ISO 8601 defines date and time separated by "T". 
Applications using this syntax may choose, for the sake of 
readability, to specify a full-date and full-time separated by 
(say) a space character."


This story about the ambiguity of ISO 8601 is the reason why 
the --iso-8601 option has been dropped from GNU date in favor 
of --rfc-3339. But that option is buggy, since it returns the 
date with a space instead of a "T"... I am filing a bug report!


Conclusion: let's use a "T", to be compatible with everyone! :-)

-- 
Romain LENGLET