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#205905 - 21/02/2004 20:43 Re: Time Zone Setting [Re: peter]
tonyc
carpal tunnel

Registered: 27/06/1999
Posts: 7058
Loc: Pittsburgh, PA
What exactly are you hoping for from a new userland?
Recently I wanted to try out a memory debugger/profiling type application but it required a more recent glibc than the empeg has. I also figure there would be performance and stability benefits from using more recent versions, but I don't keep up well enough to know if it would be a significant improvement or not.
_________________________
- Tony C
my empeg stuff

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#205906 - 22/02/2004 04:08 Re: Time Zone Setting [Re: tonyc]
alex25
member

Registered: 30/06/1999
Posts: 179
Loc: Switzerland
I'm not sure if it's worth mentioning. Maybe you talk about something completly different, but my second harddrive on my spare empeg player still contains and runs the full blown debian installation in a chrooted environment. Including apache, php, sshd, ... (http://empeg.homelinux.com)
I'm always using the latest testing debian distribution which includes at the moment gcc-3.3 and libc-2.3.2. The latest apt-update I've done was about 1 month ago. Does this help in any way?

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#205907 - 22/02/2004 04:28 Re: Time Zone Setting [Re: mlord]
peter
carpal tunnel

Registered: 13/07/2000
Posts: 4180
Loc: Cambridge, England
For a new userland, I'd simply use the latest BusyBox
Now there's a good idea. I'll look into it. Another thing I'd get round to investigating if v3 were a proper project is linking the player itself against uclibc -- there must be a load of stuff in glibc, even a static link, that we don't need. Locales, for instance. Anyone know whether uclibc gets timezones right?

Peter

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#205908 - 22/02/2004 09:33 Re: Time Zone Setting [Re: peter]
mlord
carpal tunnel

Registered: 29/08/2000
Posts: 14491
Loc: Canada
I have not looked in depth at the uClibc timezone code, but tere are some notes taken from the "glibc vs. uClibc" readme file:
time functions
--------------
1) Leap seconds are not supported.
2) /etc/timezone and the whole zoneinfo directory tree are not supported.
To set the timezone, set the TZ environment variable as specified in
http://www.opengroup.org/onlinepubs/007904975/basedefs/xbd_chap08.html
or you may also create an /etc/TZ file of a single line, ending with a
newline, containing the TZ setting. For example
echo CST6CDT > /etc/TZ
3) Currently, locale specific eras and alternate digits are not supported.
They are on my TODO list.

wide char support
-----------------
1) The only multibyte encoding currently supported is UTF-8. The various
ISO-8859-* encodings are (optionally) supported. The internal
representation of wchar's is assumed to be 31 bit unicode values in
native endian representation. Also, the underlying char encoding is
assumed to match ASCII in the range 0-0x7f.
2) In the next iteration of locale support, I plan to add support for
(at least some) other multibyte encodings.

locale support
--------------
1) The target for support is SUSv3 locale functionality. While nl_langinfo
has been extended, similar to glibc, it only returns values for related
locale entries.
2) Currently, all SUSv3 libc locale functionality should be implemented
except for wcsftime and collating item support in regex.

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#205909 - 22/02/2004 17:53 Re: Time Zone Setting [Re: mlord]
peter
carpal tunnel

Registered: 13/07/2000
Posts: 4180
Loc: Cambridge, England
/etc/timezone and the whole zoneinfo directory tree are not supported.
I've a nasty feeling that this is another way of saying "it doesn't work out for itself when DST starts and ends", which would be a real chore to implement ourselves.

Peter

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#205910 - 22/02/2004 18:28 Re: Time Zone Setting [Re: peter]
Mataglap
enthusiast

Registered: 11/06/2003
Posts: 384
When DST ended a while ago and I didn't have to change the clock in the car, that was nice. Really appreciate that. It'd be a bad feature to loose.

--Nathan

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#205911 - 22/02/2004 19:03 Re: Time Zone Setting [Re: peter]
mlord
carpal tunnel

Registered: 29/08/2000
Posts: 14491
Loc: Canada
From looking it over very quickly, it appears that so long as we supply it with a Posix style TZ variable (which can specify DST), then it might do the Right Thing. Gotta try it on something first to make sure.

Failing that, I could implement an /etc/localtime (zone file) parser to do the Right Thing rather quickly -- if we ignore leap seconds. Basically the same 20-30 lines I just put into Hijack could be dumped into a custom add-on library to handle this for the player.

Cheers

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#205912 - 22/02/2004 20:44 Re: Time Zone Setting [Re: alex25]
tonyc
carpal tunnel

Registered: 27/06/1999
Posts: 7058
Loc: Pittsburgh, PA
Yeah, that's not a bad idea for development and experimentation purposes, but I like where this conversation is going in terms of thinking about getting the standard empeg distribution updated. I can always run another environment built from scratch, but it sounds like a little elbow grease could net a much leaner and more powerful userland environment that everyone would benefit from.
_________________________
- Tony C
my empeg stuff

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#205913 - 24/02/2004 11:40 Re: Time Zone Setting [Re: mlord]
tms13
old hand

Registered: 30/07/2001
Posts: 1115
Loc: Lochcarron and Edinburgh
In reply to:

It appears to be stored in bytes 0x51 - 0x53 of the flash savearea.


Would somebody update the relevant part of RioCar.Org with this, please? The interpretation can be found elsewhere in this thread; in brief, it's a series of directory indices.
_________________________
Toby Speight
030103016 (80GB Mk2a, blue)
030102806 (0GB Mk2a, blue)

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#205914 - 24/02/2004 11:57 Re: Time Zone Setting [Re: tms13]
tonyc
carpal tunnel

Registered: 27/06/1999
Posts: 7058
Loc: Pittsburgh, PA
Would somebody update the relevant part of RioCar.Org with this, please?
Will do. I've found other bits in there too for things that aren't listed, and have updated my own copy of that Excel spreadsheet that has the flash map... Just haven't uploaded it yet. I've also answered some of the things I wasn't sure about... I'll get that page updated ASAP.
_________________________
- Tony C
my empeg stuff

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#346189 - 04/07/2011 01:10 Re: Time Zone Setting [Re: peter]
Daria
carpal tunnel

Registered: 24/01/2002
Posts: 3937
Loc: Providence, RI
Originally Posted By: peter
[color:"#FFA500"]<blockquote>/home/empeg/toolchain_binutils-2.10.1_gcc-2.95.3-arm010218_glibc-2.1.3/arm-empeg-linux/share/zoneinfo/Universal</blockquote></font>That is indeed quite embarrassing. Cross-compiling entire Linux userlands is not the black art it once was, but the glibc in car-player images hasn't been updated since before I joined Empeg, if ever. It's still somewhere waay down on my v3 wishlist to cross-compile an entire brand-new userland for car-players, with more modern bash, coreutils, glibc. and so on -- at least, if someone fixes my GCC3 PR from like 2001 or if I can get the Apple no-clone-structors patch working for 3.3.[23] for ARM. (The "real-world example" in the PR is, of course, the car-player software.)
<br>
<br>Peter
<br>


Totally fixed... for gcc 4.4 :\

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