Hurd Traffic #73 For 27 Dec 2000

Editor: Zack Brown

By Paul Emsley  and  Zack Brown

Mach 4 (http://www.cs.utah.edu/projects/flux/mach4/html/) | Hurd Servers (http://www.gnu.org/software/hurd/hurd.html) | Debian Hurd Home (http://www.gnu.org/software/hurd/debian-gnu-hurd.html) | Debian Hurd FAQ (http://www.debian.org/ports/hurd/hurd-faq) | debian-hurd List Archives (http://lists.debian.org/#debian-hurd) | bug-hurd List Archives (http://mail.gnu.org/pipermail/bug-hurd/) | Hurd Reference Manual (http://www.gnu.org/software/hurd/reference-manual.html) | Hurd Installation Guide (http://pick.sel.cam.ac.uk/~mcv21/hurd.html) | Cross-Compiling GNUMach (http://pages.hotbot.com/sf/igorkh/gnumach-cross.txt) | Hurd Hardware Compatibility Guide (http://www.urbanophile.com/arenn/hacking/hurd/hurd-hardware.html)

Table Of Contents

Introduction

Want to help write KC Debian Hurd? See the KC Authorship page (../author.html) the KC Debian Hurd homepage (index.html) , and the Thread Summary FAQ (../summaryfaq.html) . Send any questions to the KCDevel mailing list. (mailto:kcdevel@zork.net)

Mailing List Stats For This Week

We looked at 74 posts in 302K.

There were 31 different contributors. 13 posted more than once. 8 posted last week too.

The top posters of the week were:

 

1. Threading In The Hurd
14 Dec 2000 - 20 Dec 2000 (11 posts) Subject: "Threads"
Summary By Zack Brown
People: Jim FranklinMarcus Brinkmann

Athanasios Kinalis asked if pthreads (or any other threading library) were available for the Hurd. Jim Franklin replied, "The hurd uses cthreads at this time. There are plans to implement pthreads but that is at some time in the future." Roberto Diaz posed the problems of why threading needed to be visible at all. He suggested that threads could be implemented at the server layer, completely transparently to the applications programmer. Jim replied that anyone could implement Roberto's idea if they felt like it, since the project was GPLed, but he added that threading was a well-understood programming concept, and already implemented in some form under the Hurd, and so it seemed more natural to continue. Marcus Brinkmann also said to Roberto:

What you proposed has little to do with the Hurd itself. The Hurd could make use of such a functionality and replace threads usage with your new thing if it existed. But it doesn't, so we don't worry about it. Implementing such is not the focus of the Hurd project at all.

Also, it doesn't do away with the need for pthreads support. For one, pthreads is a portable standard, and as such quite useful for applications, and applications will use them. Our goal is not to convert everybody to our own way of thinking, but to enable everyone to build on top of the Hurd. So, pthreads is still needed to compile applications like the Gnome DE.

We can talk when your new stuff is implemented and integrated in gcc, gdb etc. Then we can consider if we want to use that or stick with cthreads or pthreads. Until then, you will find that around here there is not much interest in such things as in any other place were threads are used.

 

2. Status Of Hurd CD Installation Tools
14 Dec 2000 - 15 Dec 2000 (3 posts) Archive Link: "Hurd CD"
Summary By Zack Brown
People: Philip Charles

Philip Charles reported:

The transition of the Debian archive to the spool system is creating problems for the Hurd CD. Debian-cd will have to be modified to work with this and already I have noticed that sourceforge, the mirror I use, has not been updated for the the last few days. In time the new scheme will settle down, but this could be a month or two. While the transition does not affect potato (2.2_rx), it does affect woody and hurd is part of woody.

What this means is that hurd-E1.iso will be the last release until the transition to pool has settled down.

I plan to rebuild the CD shortly using the pre-pool file system and, if time permitts, rebuild the boot-floppies based on 2.2.20. I will also incorporate the new tarball. Unfortunately this means that I will have to stop developing the CD after this until the pool system is fully established.

He and Marcus both agreed that the pool system did look good in spite of these problems, and Marcus asked if Philip had contacted the debian-cd maintainers about the situation. Philip replied:

I will be contacting the debian-cd group in a few minutes. I suspect that debian-cd will need to be hacked in order for it to work with the pool system. However, prudence suggests that it would wise to wait for the transition to be completed.

At the moment my download rate seems to be slower than the rate of conversion. It seems as though sourceforge is undergoing a reorganisation and is slow. My ISP is also slow at the moment.

 

3. Rereading A Partition
18 Dec 2000 (5 posts) Archive Link: "rereading a partition"
Summary By Paul Emsley
Topics: FS: ext2
People: Glenn McGrathNeil WalfieldMarcus Brinkmann

Glenn McGrath wrote:

I've been working on a simple fdisk like program, I'm stuck trying to workout how to get the program to reread the partition table.

In linux there is an ioctl defined as BLKRRPART which works, i found something similar called V_REMOUNT in /include/mach/machine/disk.h, the comment says it remounts a drive.

When i try and use V_REMOUNT perror reports that its not apropriate for the device, i cant remember the exact message now, but it was words to that effect.

Whats the correct was to get hurd to rescan the disk after the partition table has changed ?

Neil Walfield replied:

At the moment, it is not the Hurd but rather Mach which manages partitions. My understanding is that there is no way to force it to reread the partition table -- only a reboot. Even if this feature was added to Mach, the storeios for that device would need to be restarted and this is, of course, something that the kernel knows nothing about.

The Hurdish way to solve this problem is in userspace via a translator. A server, let's call it `disk_part', would translate a harddrive based on the partition table possibly creating a hierarchy as follows:

 
  /dev/hda   <-- disk_part
          /1 <-- store_io 
          /2 <-- store_io 
          ...

File servers would attach to the respective store_io. When a program attached to /dev/hda, it could ask to own the disk and the store_ios would be shut down. The program would then modify the partition table and upon detach, the stores would be restarted (as would their respective translators).

Marcus Brinkmann liked this cool and Hurdish approach. However:

But there is one glitch. We need to be able to open the root filesystem at bootstrap (for example, ext2fs.static). Maybe the functionality should be put in a library, and enable libstore to make use of it, so you can either do what Neal says above or, alternatively, specify the partition format and partition directly to libstore and have a 'partition' store type. This circumvent the above scheme, but only for bootstrap. I mean like this:

ext2fs -T partition dos,1:device:hd0

instead

ext2fs -T device hd0s1

 

4. Scripts For Status Of Hurd Port
18 Dec 2000 - 19 Dec 2000 (2 posts) Archive Link: "Scripts for status of Hurd port, apt update"
Summary By Paul Emsley
People: Jason FeliceMarcus Brinkmann

Jason Felice brought our attention to the porting tools quinn-diff, buildd, and andrea. In reply Marcus Brinkmann mentioned his turtle (http://sourceforge.net/projects/turtle) and encouraged Hurd porters to use it.

 

5. Tanslator Debugging
19 Dec 2000 (2 posts) Archive Link: "First go at a translator"
Summary By Paul Emsley
Topics: FS: FTPFS
People: Igor KhavkineMarcus Brinkmann

Igor Khavkine decided to write a gopherfs translator using ftpfs and libnetfs as a basis. "I've written most of it and i'm trying to run it and see where things break, but whenever I try to settrans it on some node and do ls, it blocks. When I try to attach gdb to it, and the resume execution, it produces an illegal instruction error in the thread library. "

Marcus Brinkmann replied: "After attaching, use info threads to see which thread is stuck, and then thread N, bt to see where it stucks. This should help. Post the gdb output of your session next time, so we have some hard facts. "

 

6. Links Broken On Hurd Page
19 Dec 2000 (2 posts) Subject: "Links broken on Hurd page."
Summary By Zack Brown
People: Jason M. FeliceJim Franklin

Jason M. Felice reported, "A number of links on the GNU Hurd pages are broken. Links from http://www.gnu.org/software/hurd/howto/, specifically. It looks like the page is using relative links that expect to be up one directory." Jim Franklin replied, "I forwarded it to web-hurd@gnu.org for you. I am sending this message to help-hurd@gnu.org so other folks know where send this type message." End of thread.

 

7. HURD Installation Image
19 Dec 2000 - 20 Dec 2000 (2 posts) Archive Link: "image CD"
Summary By Paul Emsley
People: Petros SidiropoulosPhilip Charles

In reply to a question from Petros Sidiropoulos, Philip Charles said that the Hurd CD image can be found:

 

 

 

 

 

 

Sharon And Joy
 

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