Date: Fri, 22 Dec 2000 12:02:34 +0200
From: "Eli Zaretskii" <eliz AT is DOT elta DOT co DOT il>
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In-reply-to: <ku454tke181c70f6rimuamfd2pc9p0blfk@4ax.com> (message from Jason
	Green on Thu, 21 Dec 2000 23:52:44 +0000)
Subject: Re: strftime: Need Help with Time Offsets
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> From: Jason Green <news AT jgreen4 DOT fsnet DOT co DOT uk>
> Date: Thu, 21 Dec 2000 23:52:44 +0000
> 
> > > There appears to be a bug in strftime() when using the %z format.
> > 
> > The bug, whether it exists or not, does not necessarily have anything
> > to do with what Felix reported: I replied to his message saying I
> > cannot reproduce the problem.  His test program wroked for me.  I
> 
> Perhaps you could try my test program too, and tell if it does what
> you expect it should?

I get similar results to what you reported:

    Fri, 22 Dec 2000 09:53:58 +0000 GMT
    Fri, 22 Dec 2000 11:53:58 +7200 IST
    Thu, 21 Dec 2000 21:19:58 -0000 TEST1
    Fri, 22 Dec 2000 22:27:58 +38040 TEST2

I.e., the issue with negative offsets is reproducible.  But that's not
what the original message was talking about, IIRC.  The results in the
original message were completely bogus, which I couldn't reproduce.

> The POSIX Programmer's Guide isn't too helpful on this matter.  It
> lists: "%z Time zone.", %Z isn't listed.
> 
> The Linux man page for strftime() is better:
> 
>        %z     The time-zone as hour offset from GMT.  Required to
>               emit  RFC822-conformant  dates (using "%a, %d %b %Y
>               %H:%M:%S %z"). (GNU)

The library used by GNU/Linux systems, the glibc, already supports the
new C99 ANSI standard, which codifies the %z format.  The DJGPP
library is much older than glibc, and doesn't yet support C99; the
lack of support for %z is a minor nuisance compared to some major new
functionality that C99 warrants but DJGPP doesn't support.

Volunteers are welcome to work on adding C99 functionality to the
library.

> Maybe you have a copy of the ANSI standard to check on this?

It isn't mentioned at all in ANSI C89, which is what DJGPP supports.
And the info in Posix doesn't tell anything about the units, as you
cite above.