Getting an old IBM 3151 terminal working with Debian Squeeze
I bring my laptop with me to St. Louis for Christmas every year. In St. Louis I have a big pile of obsolete equipment. One particular piece is an old IBM 3151 Terminal with Wyse 50 emulation card installed.
I like to hook up the IBM 3151 terminal to my laptop to give me an extra text only display and keyboard for editing text files and chatting on IRC etc.
Since this terminal (with the emulation card I have on hand at least) does not handle VT100 escapes it is a bit of a bear to set up so I figured I would write a blog post about how I get it working under Linux.
I like the nice crisp lime green display and the wonderful model M style buckling-sping keyboard.
First plug the serial cable into the rear left hand port (left hand side with the front of the display facing you) the other port is for a serial printer if you have one.
Next type Ctrl-Setup to get to the setup screen. You will use the arrow keys to move around the menu and the space bar to choose the options, once you have selected everything you want on that screen press send to go to the next setup screen.
Machine Mode: WYSE50/50+ Enhance Mode: ON Screen: NORMAL Row and Column: 25 x 80 Scroll: JUMP Auto LF: OFF CRT Saver: ON Line Wrap: ON Attribute: SCREEN Return/Enter: CR/CR Protect: HALF-INT
Operating Mode: ECHO Line Speed (bps) 9600 Word Length (bits) 8 Parity: NO Stop Bit: 1 Parity Check: OFF Line Control: PRTS Pacing: OFF Block End: US/CR Edit Mode: DUPLEX Keyboard Lock: ENABLE
Just ignore this screen if you don't have a printer, it only has the serial port setting for the printer on this screen anyway.
This is the screen that allows you to save your settings. Just press space over the desired function in order to perform it.
You will want to highlight save and press space and then highlight reset and press space on this screen.
The other functions are fairly obvious in what they do. you can search google for the 3151 manual to get full docs on this terminal.
Now that the terminal is set up you just have to get init to spawn a getty for the terminal and you will get a login prompt on the terminal. Once you have completed this step we are nearly finished.
Add this line to your inittab and when you are finished type init q as root.
T0:23:respawn:/sbin/getty -L ttyUSB0 9600 wyse50
Once you have typed init q you should see a login prompt on the terminal. go a head and log in and you should have a shell. a lot of curses programs, including the pager will act funny though because they seem to assume that the whole world is a VT100 compatable terminal. The next section addresses how to fix this.
The siple answer to getting the terminal to behave as much as possible like a VT100 to applications that are poorly written is to simply use screen to translate those vt100 escapes into wyse50 escapes. just simply invoke screen -a -O once you log in and curses applications should start to behave normally.
I hope this helps someone else that has a similar Terminal that they want to use on a linux machine. I also have a nice AT&T 705 MT terminal I could have used that has excellent VT100 emulation, but I prefer the model M keyboard on my 3151. In the future I might find the DEC emulator card for it at a reasonable price and just simply use that instead and save the headache of using screen.
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Getting Suspend to disk working on Debian 6.0 Squeeze on the Thinkpad T41
A recent update to the 2.6.32 i486 kernel in Squeeze had the effect of making the kernel crash on resume from disk. I tracked things down to http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=607288
This basicaly boils down to adding acpi_sleep=s4_nohwsig to the kernel command line.
While I'm at it I thought I would describe how I have suspend to disk set up on my T41 since I had to do other things to get hibernate to work at all before this.
Step 1. pre/post suspend script
I crated a file named 20_deep13hibernate inside of /etc/pm/sleep.d/ it looks like this:
#!/bin/sh
# Action script ensure that unattended-upgrades is finished
# before a hibernate
#
# Copyright: Copyright (c) 2009 Michael Vogt
# License: GPL-2
#
PATH=/sbin:/usr/sbin:/bin:/usr/bin
# pm-action(8) -
#
# On suspend|hibernate, disconnect any wpa-roam managed interfaces,
# reconnect it on resume.
case "${1}" in
hibernate)
echo removing wireless module
modprobe -r ipw2200;
pccardctl eject;
;;
resume|thaw)
# nothing
echo loading wireless module
modprobe ipw2200;
pccardctl insert;
;;
esac
Next Just edit /etc/default/grub and change the line that looks like:
GRUB_CMDLINE_LINUX_DEFAULT="" to
GRUB_CMDLINE_LINUX_DEFAULT="acpi_sleep=s4_nohwsig"
Finally just run update-grub and suspend to disk should work now. You may also want to add other modules into the sleep.d script (particularly if you have a different wifi card inside your Thinkpad T41) I hope this helps someone with a isimilar problem.
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mod_tcpwrapper -- tcpwrapper support for Lighttpd
As mentioned in a previous post I have recently moved to a Debian squeeze box. This squeeze install is inside of an OpenVZ container so (as far as I know) I can't use tools like fail2ban to edit firewall rules. tcpwrappers works pretty good though as long as your services support it.
I'm already using the denyhosts package to ban people attempting to brute force the ssh service. so I figured I would set up lighty to use tcpwrappers as well.
When I did I found out that lighttpd does not currently have any tcp wrapper support. so I made this little lighttpd module to implement it.
Here is the diff between my code and the mod_skeleton.c file it is based off of
wschaub@deep13TP:/tmp/mod_tcpwrapper$ diff -u ../lighttpd-1.4.28/src/mod_skeleton.c mod_tcpwrapper.c
--- ../lighttpd-1.4.28/src/mod_skeleton.c 2010-08-17 05:04:38.000000000 -0400
+++ mod_tcpwrapper.c 2011-09-02 18:03:26.000000000 -0400
@@ -7,16 +7,15 @@
#include <ctype.h>
#include <stdlib.h>
#include <string.h>
+#include <tcpd.h>
/**
- * this is a skeleton for a lighttpd plugin
- *
- * just replaces every occurance of 'skeleton' by your plugin name
- *
- * e.g. in vim:
- *
- * :%s/skeleton/myhandler/
+ * mod_tcpwrapper by William Schaub <wschaub@steubentech.com>
+ * This module works like mod_access only it has no configuration parameters
+ * Instead it uses the TCP wrapper library to allow/deny access to the lighttpd
+ * daemon in /etc/hosts.allow and /etc/hosts.deny
*
+ * This module is under the same license as Lighttpd
*/
@@ -55,7 +54,7 @@
}
/* init the plugin data */
-INIT_FUNC(mod_skeleton_init) {
+INIT_FUNC(mod_tcpwrapper_init) {
plugin_data *p;
p = calloc(1, sizeof(*p));
@@ -66,7 +65,7 @@
}
/* detroy the plugin data */
-FREE_FUNC(mod_skeleton_free) {
+FREE_FUNC(mod_tcpwrapper_free) {
plugin_data *p = p_d;
UNUSED(srv);
@@ -97,12 +96,12 @@
/* handle plugin config and check values */
-SETDEFAULTS_FUNC(mod_skeleton_set_defaults) {
+SETDEFAULTS_FUNC(mod_tcpwrapper_set_defaults) {
plugin_data *p = p_d;
size_t i = 0;
config_values_t cv[] = {
- { "skeleton.array", NULL, T_CONFIG_ARRAY, T_CONFIG_SCOPE_CONNECTION }, /* 0 */
+ { "tcpwrapper.array", NULL, T_CONFIG_ARRAY, T_CONFIG_SCOPE_CONNECTION }, /* 0 */
{ NULL, NULL, T_CONFIG_UNSET, T_CONFIG_SCOPE_UNSET }
};
@@ -130,7 +129,7 @@
#define PATCH(x) \
p->conf.x = s->x;
-static int mod_skeleton_patch_connection(server *srv, connection *con, plugin_data *p) {
+static int mod_tcpwrapper_patch_connection(server *srv, connection *con, plugin_data *p) {
size_t i, j;
plugin_config *s = p->config_storage[0];
@@ -148,7 +147,7 @@
for (j = 0; j < dc->value->used; j++) {
data_unset *du = dc->value->data[j];
- if (buffer_is_equal_string(du->key, CONST_STR_LEN("skeleton.array"))) {
+ if (buffer_is_equal_string(du->key, CONST_STR_LEN("tcpwrapper.array"))) {
PATCH(match);
}
}
@@ -158,10 +157,11 @@
}
#undef PATCH
-URIHANDLER_FUNC(mod_skeleton_uri_handler) {
+URIHANDLER_FUNC(mod_tcpwrapper_uri_handler) {
plugin_data *p = p_d;
int s_len;
size_t k, i;
+ struct request_info request;
UNUSED(srv);
@@ -169,38 +169,33 @@
if (con->uri.path->used == 0) return HANDLER_GO_ON;
- mod_skeleton_patch_connection(srv, con, p);
-
- s_len = con->uri.path->used - 1;
+ mod_tcpwrapper_patch_connection(srv, con, p);
- for (k = 0; k < p->conf.match->used; k++) {
- data_string *ds = (data_string *)p->conf.match->data[k];
- int ct_len = ds->value->used - 1;
+ /* init the request struct using the fd of our current connection */
+ request_init(&request, RQ_DAEMON,"lighttpd", RQ_FILE,con->fd, 0);
- if (ct_len > s_len) continue;
- if (ds->value->used == 0) continue;
-
- if (0 == strncmp(con->uri.path->ptr + s_len - ct_len, ds->value->ptr, ct_len)) {
+ /* Fill in the fromhost bits of the request struct */
+ fromhost(&request);
+ /* Access blocked by tcp wrappers */
+ if(!hosts_access(&request)) {
con->http_status = 403;
-
return HANDLER_FINISHED;
- }
}
- /* not found */
+ /* Access allowed */
return HANDLER_GO_ON;
}
/* this function is called at dlopen() time and inits the callbacks */
-int mod_skeleton_plugin_init(plugin *p) {
+int mod_tcpwrapper_plugin_init(plugin *p) {
p->version = LIGHTTPD_VERSION_ID;
- p->name = buffer_init_string("skeleton");
+ p->name = buffer_init_string("tcpwrapper");
- p->init = mod_skeleton_init;
- p->handle_uri_clean = mod_skeleton_uri_handler;
- p->set_defaults = mod_skeleton_set_defaults;
- p->cleanup = mod_skeleton_free;
+ p->init = mod_tcpwrapper_init;
+ p->handle_uri_clean = mod_tcpwrapper_uri_handler;
+ p->set_defaults = mod_tcpwrapper_set_defaults;
+ p->cleanup = mod_tcpwrapper_free;
p->data = NULL;
You can download a tarball with the source code, config files and instructions as well as pre-compiled modules for i386 and sparc (compiled for Debian squeeze) at this link mod_tcpwrapper.tgz
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I retired my last Solaris machine yesterday.
I have been using Solaris (both on the desktop and on the server) mainly on SPARC hardware since the late 90s. I think it was a great platform and still could be if Oracle didn't pretty much own it. Sometime last year they closed Security patches to the public and wanted insane amounts of money per machine just for the ability to download patches.
This web server ran Solaris 10 Until some time after noon yesterday when I moved it to the most recent Debian stable release. I was thinking of making it a FreeBSD server instead but since I have been doing a lot of work on Debian and Debian based systems lately it seems like a nice fit. Particularly with it's long release cycle and long term support with security patches.
I really want to get back into FreeBSD again sometime though, Hopefully I will have an excuse to do so soon.
As far as Debian goes I'm really impressed with it, I've been running it on my old ThinkPad T41 and on my SunBlade 2000 and I really have no complaints about it. It's very well put together and most of the packages are well thought out and integrated into the system. Everything that goes into the system has to follow a strict policy which is well documented, most everything you need by design is installed into /usr/share/doc/packagenamehere. I couldn't be happier, particularly now that I don't have to compile the majority of the packages that I use anymore.
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I have recently started working part time with Genesi and got involved with an ongoing project of theirs that overlaps with the goals of my TEOTWAWKI Net project. You can read about it at:
I started out as Genesi customer purchasing and getting really excited about their amazing Smart Book and Smart Top products and started making some SD card based demos for the products including a Sugar image, a live SD card image and a headless image.
I found myself at the Genesi Genesi scrum in San Antonio this past June and was asked to help out with this Project in Tanzania.
I applied a lot of the research and development that originally went into TEOTWAWKI Net since 2009 to meet the requirements of this project. Although TEOTWAWKI Net is not integrated into the solar outpost project (yet) A lot of the technologies in the prototype system are there.
The ideas is fairly simple. We send down a solar power system and a collection of low power wireless gear, Efika MX smart tops and smart books and a collection of software that allows them to collaborate and create their own library of content even if there is no existing infrastructure.
The heart of the system is the Efika MX smart top which is a very tiny ARM based machine (running on the Freescale i.MX51 system on a chip) It draws about 4 watts of power when idle and maxes out at around 10 watts, has no fans or any other moving parts, generates almost no heat, has ethernet, wireless, HDMI, USB and built in audio.
We use the Efika MX smart top as a headless server which provides:
All of this combined gives this classroom in a village without grid power the ability to develop course material and collaborate using Efika MX smartbooks over the local wireless AP. the Solar system can be use to re-charge the smart books as necessary and to run the standalone server the rest of the time.
Thanks to the power efficiency of these ARM chips and the flexibility of Linux this is doable with a very modest bare bones Solar system. The server/wireless gear should be able to run all day and as long as the sun shines we should be putting in more power than we take out. The smartbooks can run almost 7 hours on a single charge and don't take long to charge back up to full.
I'm really excited to be working on a project in the real world related to the work I've been doing in my spare time these last few years.
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Bluetooth Essentials For Programmers Review
If you have been following my TEOTWAWKI Net project you will know I'm interested in dynamically formed short range wireless networks and so of course bluetooth seems natural to explore. To help me get started I purchased "Bluetooth Essentials For Programmers by Albert S. Haung & Larry Rudolph ISBN 978-0-521-70375-8"
I thought I might review this book a bit and mention what it covers vs what it leaves up to the reader to figure out.
This book is great to get you started writing code that actually does something very quickly and has great examples in Python, Java, C and objective C. For that reason alone I think it is worth it to buy if you want to get started quickly writing bluetooth applications. Here's a short list of whats covered.
While it is still a great help for someone wanting to get started with Bluetooth I think they could have gone a bit further than they did its really a basic bluetooth tutorial in book form and it does that well but I think a more expanded edition of the book should be made covering the following topics.
If I have time I plan to cover some of these topics that aren't covered in bluetooth essentials once I have finsihed R&D on the bluetooth support in the future versions of TEOTWAWKI Net.
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As noted on the wiki and on facebook. Thanks to the generous contributions of Fred Grose I got my First rooted HTC Dream phone on Saturday and the second one today. Being someone who is very behind the times as far as mobile technology goes this 2 year old smart phone really impressed me. It's also highly addictive even without any cell service.
So far I haven't written one line of code for the platform yet but putting it through its paces has been very fun. There's so much this thing can do out of the box that I'm sure Apple is in big trouble. particularly since this platform is open source friendly. (That is the main reason I chose this as my first smart phone platform to develop for)
This phone also has me thinking about ARM based machines and how I would really love to have a good ARM netbook with similar capabilities (but with a regular Linux distro and lots more ram and flash space and a bigger screen of course) Hopefully we will see some come onto the market soon. until then I have one heck of a powerful and flexible machine that fits in my pocket! something I have wanted for many years is now a reality.
I still want to own an open pandora one day but this is close enough for what I want to do for now.
I'm done rambling now more info when I finish the python re-write and get serious with the droid. My project will need to use the NDK for various reasons and I should be learning all about android internals soon. I will post more on my blog about android internals that I find interesting as I run across them.
I also wanted to thank the author of the Super E ROM I had no end of trouble with cyanogen 6.0 but Super E seems be nice and solid. It leaves me at android 2.1 but I'm sure the 2.2 roms for the dream will get better by the time I will care about having a 2.2 machine.
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I finally forced myself to sit down today and I re-implemented about 90% of the mapper daemon today. If I keep things up at this rate we might actually see a real sugar activity version of TEOTWAWKI Net soon.
I still have the following milestones to complete
Once I have a working sugar activity I will release a standalone Linux version and see what can be done to make it work under windows and hopefully smart phones.
I need at least one USB bluetooth dongle and two rooted HTC dream phones (also known as the G1 phone) to get started on the android version.
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I just made some amazing hot wings in the crock pot yesterday.
This is what I did:
I needed two batches of sauce to cover my wings.
Cover the wings with the sauce and stir to make sure all the wings are covered and set the crock pot on high for 2 and a half hours. (do not take the lid off to check until at least the 2 and a half hours are up!)
Check and make sure the wings are done by taking out a wing and testing it.
Once the wings are fully cooked separate the wings and the sauce. transfer the the sauce to a sauce pan and boil it down as much as you can and then thicken it back up like you would making gravy. (I used flour, but you might also try corn starch, it came out good with flour)
I came up with this because I could not find any good recipes for hotwings that only used a crockpot.
I wasn't expecting it to turn out so good so that's why I'm posting it to here. The end result is a lot like buffalo wings except its
tender and has a really nice flavor. It is greasy but then so are buffalo wings.
I found the sauce to be so good that I ended up just soaking it into bread rather than wasting it.
If you try it let me know what you think.
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Whenever I get involved with something I like to study it's history for me that means finding the earliest copies of the software and sources.
I decided today to find a copy of the original B-News software and spent a few hours pulling my hair out since ftp.uu.net seems to be no more.
Finally I managed to find copies of A news B news and C news plus the nntp reference implementation. In the interests of posterity I am hosting a copy of the software I found here
I hope I save someone from pulling their hair out.
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Thunderbird 3.x preferences rant
I really like Thunderbird so don't get me wrong here. However I just have to rant a bit about the user interface for configuring this particular mail client.
To their credit they do have most everything you would want in the GUI. Except one thing I really needed, a way to set the font size for the list of emails and other things that are part of the user interface not just the message body text.
I know some people will say "but look a simple google search tell you how to do that! Why are you complaning?" I'm complaining because things like this should not require editing a config file! I like that its customizable by a CSS file thats a wonderful thing. But you can't tell me that this couldn't have been editable in the preferences GUI. I have nothing against config files I like being able to do cool things with config files but this is 2010 not 1992! Evrything doesn't need to be in a GUI but I would expect that basic look and feel modifications, like the font size of the list of emails would be configurable from the GUI. Is that too much to ask for in the 21st century?
Maybe I'm getting spoiled these days but I'm sure people considering an open source mail client are put off by things like this. I know they are because I actually got asked by the person whom I was increasing the font size for "Is it difficult to config that option because it's open source?"
Anyway I still love Thunderbird I just hope that they will fix things like this in newer releases.
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I really tried to be upbeat about Oracle acquiring Sun Microsystems. I thought for sure that they would do all they could to encourage wide use of Solaris and would invest heavily on Solaris and the SPARC platform.
Whether or not they invest in Solaris and Sun's hardware platforms remains to be seen but one thing is now every clear. They have no intentions whatsoever of treating their customers and potential customers with respect.
Instead they decide that they should handle support and licensing just like they do with their other products. This includes charging well over $300 a year for access to critical security patches.
I have been a long time fan of Solaris over the years and still think it has a lot of merits technically. But those merits mean nothing to me if I'm forced to pay for security patches. There are a lot of small shops out there running Solaris that don't want or even need the hassle of a full support contract just to get patch access.
I might feel a bit better about this if you could simply pay for only basic sunsolve access to documentation and patches only and do self-support. for a reasonable price (say $50 to $100 a year) but charging over $300 a year for something we used to to be able to do ourselves for free is just insane.
I also consider blocking access to security patches to be irresponsible. The net is more hostile than ever today and there will now be even more unpatched Solaris boxes out there just waiting to be rooted, and all because Oracle wants to squeeze as much as possible out of Sun's remaining user base.
So as much as it pains me to do so I will be moving off of Solaris on my web server and switching either to CentOS or one of the BSD flavors. I will still run Solaris on my desktop system on my private network but I think my love affair with Sun has just been killed by Oracle. Thank you Oracle for taking a great company like Sun with tons of talent and some of the best most innovative technology out there and killing it by forcing it to conform to Oracle's culture.
It's been a great ride but I feel that Sun will share the same fate as DEC unless Oracle changes It's ways and soon. RIP Sun Microsystems 1982-2010 you will be missed.
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AgeStar CFB3AT FireWire Enclosure problems in Solaris
I recently needed to add a new external disk to my SunBlade 2000 I had a spare 500GB SATA drive laying around and I found a drive enclosure that supports both PATA and SATA drives and has USB 1.0, 2.0, Firewire 400 and E-SATA connectors on it. at http://www.cooldrives.com/esu sb20andfi.html
I had nothing but trouble with it under Solaris 10/SPARC but it ran perfectly
fine on Linux, Windows and MacOS X.
I would get the following errors when copying lots of data to this drive:
scsi: WARNING: /pci@8,700000/firewire@5,2/unit@0050770e00071002/disk@0,0 (sd37):
Oct 11 22:27:04 ayeka SCSI transport failed: reason 'reset': retrying command
Oct 11 22:27:05 ayeka transport rejected fatal error
Oct 11 22:27:05 ayeka ufs: WARNING: Error writing ufs log
Oct 11 22:27:05 ayeka ufs: WARNING: ufs log for /mnt changed state to Error
Oct 11 22:27:05 ayeka ufs: WARNING: Please umount(1M) /mnt and run fsck(1M)
I did a ton of fiddling around and finally I have success! I had to dig around the opensolaris.org code browser looking at the scsa1394 driver. There is an undocumented driver variable called scsa1394_wrka_fake_rmb
Don't ask me what it does exactly all I know is it is off by default and setting it to 1 instead of 0 seems to have fixed my issue. Or at least somewhat anyway. I had it cloning my LaCie BigDisk for most of last night and it did eventually die. I'm going to try re-enabling the symbios workaround and see if that fixes it completely. In the mean time I'm using rsync to do the copy and it seems to be reliable enough to replace my ailing LaCie drive. If things continue to be a big PITA I will just install a USB 2.0 card in my Sun and be done with it.
This tip should work with any enclosure that uses a Prolific Technology Inc. PL-3507 chipset but YMMV. I hope someone finds this info useful because I sure wish I had found it before having to get elbow deep into the guts of Solaris out of frustration.
To set this yourself try putting the following lines into /etc/system and rebooting. I'm not sure that scsa1394_wrka_symbios = 0 is needed.
*Try some FireWire system tuneables
set scsa1394:scsa1394_wrka_symbios = 0
set scsa1394:scsa1394_wrka_fake_rmb = 1
For more information on using firewire drives with SPARC machines take a look at This article
[/solaris/firewire] permanent link RSS feed
Open Pandora an idea who's time has come
I just stumbled across the Open Pandora Project and I am practically drooling over this awesome wonder of a device. It is unfortunate that it is primarily focused on gaming because this little gem is capable of so much more!
This little device fits in your pocket, has blue tooth and 802.11 wireless technologies, a battery life around 10 hours. two SDHC slots, two USB ports, an S-video out etc. In short it is the pocket sized general purpose computer (Super PDA if you will) that I always dreamed of ever since those Casio organizers came out. (I always wanted a Casio organizer that could run DOS or UNIX back in the early 90s)
If the first batch starts shipping and the orders keep coming in for this device I am sure to scrape up the cash to get one. This is the perfect device to run TN and a bunch of other applications that are perfect for a pocket sized device like this.
I still plan to get a nice ARM based netbook as well but the awesome possibilities of this device can not be under-stated. It is easily as powerful (actually a lot more powerful) than an OLPC XO-1. and can use blue tooth keyboards etc. It has the same 256MB ram limitation as the XO-1 but if you know what you are doing you can still cram a crap load into that considering that in the 90s I had useful unix workstations running on much less than that.
I believe that powerful, open and compact general purpose devices like these that are completely open source are the future. versatile mobile computing devices and fresh new ways that we will be looking at mobile networks will change the world.
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I haven't posted anything on TEOTWAWKI Net in a while so here's an update:
I've been working on the USB sync manager which is simply a script that looks for mount points being added in a certain directory. it then scans that mountpoint for spooled up batch files containing news articles.
Once it finds the batched up articles it reads them in and deposits it's own articles onto the mounted device. once it is done processing all found mount points it will pop up a GUI (optional) listing all found mount points with an unmount button next to each one. This menu will disappear as soon as it starts processing again. The menu will not pop up if there are no more mount points left in the directory it looks in.
USB keys left plugged in will accumulate any new articles that arrive either by the network or by other USB keys being plugged in.
What I just wrote about is not just an idea but is already working now and is in CVS. I just got a lot of this working over the weekend and some more tonight.
I plan on making some changes to how the system is packaged and splitting some things out of start.sh and writing some new documentation to put in the webroot before I build more packages. At that point I might have my first numbered release. Stay tuned.
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Had fun repackaging OpenDX for Slackware today
I spent about 3 hours re-packaging OpenDX to run on Slackware for a customer today. It was nice to just get back to some good old fashioned UNIX admin work for a change.
Some people may hate the Slackware package management system or accuse it of just being a tar file (or being nonexistent) but they would only be partly right.
In Slackware package files are just tar files but the real brains behind the packaging is inside the package utilities themselves. The packaging utilities are wrappers around tar and maintain a catalog of files installed with a package so that it can be removed or upgraded later. They also can execute shell scripts included in the tarball inside of the install directory. There is no dependency tracking but the same can mostly be said of System V Release 4 packages (as used on Solaris)
Either way love it or hate it the Slackware package system is very easy to work with as a result of it's simplicity. build your project into a directory tree that reflects how the files should look relative to the root file system. put any extra needed stuff inside the install directory and build it with makepkg and you are done.
You can even use rpm2tgz to transfer an rpm into a regular tar file and work off of that if you have to. or just build the tar yourself without makepkg and still get the benefit of being able to uninstall it using removepkg later on.
I subscribe to the idea that small and simple is beautiful. Slackware packages may be lacking in modern features but they are simple and easy to work with which I find quite refreshing in this age of horribly complex software.
[/slackware] permanent link RSS feed
I found a fascinating open source hardware and software project called Arduino that has a surprising amount of sophistication and peripherals available for it. and a seemingly easy to use software development environment.
One of the options is to hook it up to blue tooth or 802.11 wireless modules. I'm thinking that I might be able to take the 802.11 or blue tooth modules (802.11 module supports TCP/IP so it is the obvious choice) and if an SD card can also be utilized I might be able to implement a cheap hardware device that can be placed in your pocket and gather/propagate TEOTWAWKI Net completely unattended. you could then sync it with your laptop or other larger system later.
I have no idea if the Arduino is capable of anything as complex as TN but it was enough to get me thinking. Eventually I would like to implement the network on smart phones and sophisticated PDA devices but open source hardware platforms like this really open a lot of cool possibilities.
I just spent a couple of hours looking at information about the platform and the microcontroller chip it is based on and it may be a bit too simple to do what I want. however It is still quite capable and flexible for small projects. I really want to see a lot more work being done in the open source hardware area. the amount of new and innovative hardware and software projects that could be built really is unlimited with completely open hardware to build on.
What i would really like to see is a project very much like Arduino but targeted at much larger scale applications. Something that is about the same size as the Arduino and has the ability to plug in multiple I/O boards with storage, wifi, etc. as well as exporting various pins you would find on a micro controller. It would also need to be able to run a decent real time OS (hopefully something POSIX like or even a small version of Linux). I could do a lot with a device like that.
In a nutshell what I would really like to see the hardware hackers come up with is a low cost general purpose embedded computer platform that is small enough to fit in someones pocket and run off of batteries. With enough CPU horsepower and features to run complex wireless network applications. I don't even need a display or a keypad but a modular system would make this easy to add. If the open source hardware hackers ever come up with such a thing I will be very happy.
I'm still tempted to buy some of these kits and see just how far I can push things though. (If only I had unlimited time!)
Ohhhh Yeahhhh! check this out: http://blogs.leaflabs.com/2009/
This looks like it may well just fit the bill for what I'm wishing for I will be following the development of this project very closely. My main focus is to get the UNIX version of TN working as well as I possibly can before I go off on porting to other platforms embedded or otherwise. but once that goal is accomplished I will be getting some kits and exploring the possibilities.
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New packages released for the LUGOR/OLPC picnic this Saturday
The packages are built from the code with the lugorpicnic tag in CVS this version includes the new and improved network mapper and sync dispatcher and an important bugfix to the syncnews.pl script (I got the article date and article arrival time backwards when reading the history file) Also as a consequence of the IPC provided by the new network mapper. the network neighborhood is now implemented as a PHP script that reads the network map from the daemon and works much better now.
The new IPC mechanism also allows the syncnews.pl script to update a "lastsync" timestamp in the network map when it successfully syncs with a node. This fixes another problem I had with the old mapper script that could cause some articles to never be sent out to other nodes.
This release also includes the incredibly useful socat utility which can be used to talk to the network mapper socket and for just about anything networking related you can think of.
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The new network mapper/sync dispatcher has just been committed to CVS. It implements everything I talked about in the previous blog post. the following are the implemented commands for the /tmp/TNmapper IPC socket.
all commands close the socket when they are finished.
UPDATE will return ACK\n on success and NACK\n on fail.
NTOA will return the ip address followed by \n or NACK\n if the nodename is not in the n2a hash.
ATON will return the nodename followed by a \n or NACK\n if the ip address is not in the map hash.
DUMP will return multiple lines containing the entire network map. it is comma separated into the following fields ipaddr, nodename, services Once it is finished dumping the socket is closed. it can return zero lines for an empty network map.
DEBUG This will output the %map and %n2a hashes to the IPC socket in Data::Dumper format.
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Looks like I have to write a comment system.
This is partly my fault because I either don't understand something or I just had to pick the most obscure blogging platform out there. But I have yet to find a comment plugin for blosxom that actually works or has understandable documentation. All of the plugins I have found are either totally undocumented or woefully out of date.
So I'm just going to have to roll my own comments system You will just have to wait until I get around to it. (I have some general ideas on how to get this done)
I normally wouldn't bother but I rather like the way blosxom does things and wordpress is a giant bloated mess. I just want to get back to simple software with a small footprint modern software is driving me crazy and I'm just sick of it.
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A new and improved Network mapper/Sync dispatcher
I've been busy learning a lot more about sockets programming from W. Richard Steven's UNIX Network Programming 1st edition. and applying some of that info to perl. I am modifying an example server that uses select and non blocking I/O to eventually be the new network mapper and sync dispatcher. I already have this test server accepting both UDP connections and AF_UNIX (local system only accessed by unix filesystem paths, (/tmp/afunixsocket for example)) streaming connections and passing them to different handlers.
The end result will be that other processes will be able to communicate with the heart of the TN system and get information about the network and be able to update the crucial time stamp information for each node (the syncnews.pl script needs to be able to do this since it is spawned into the background.)
The reason I'm focusing on this change is that the original script for the network mapper and sync dispatcher just does not seem to be easily extendable the way it currently exists and some of my testing has brought up certain design problems that can cause articles to be lost and the only way forward will be to have the mapper support IPC and add more information to the network map that can be accessed and updated by processes that need to know about and work with this information.
I have wanted to do this from the beginning anyway with the network neighborhood. it is much better to make that a script that gets info from the network map directly. instead of an ugly hack where the mapper daemon re-writes a static html file when it updates the network map.
The new way the process will work will also allow things like a name service switch plugin to be developed that will allow hostname lookups to use the TN network map.
I'm also going to make it a bit of a hybrid server in that while it does select and non-blocking I/O instead of forking. it will only do so for receiving the UDP broadcasts that build the map and handling commands from the AF_UNIX socket that update the map. any other commands will cause it to fork a process that will block and process all other commands namely dumping of the network map and doing specific map lookups. that way the main daemon will not have it's time taken up by queries about the map and since that is handled in a child process that child will only have a copy of the network map at the time of the fork. I also found a really awesome tool that blows away netcat called socat that I think I will include in the TN system for debugging and possibly other purposes later. not only does it allow me to interactively send data to and read from AF_UNIX sockets but it is an incredible networking swiss army knife that allows all sorts of different possible socket combinations to talk to each other.
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I have dug out xfig and made some simple figures showing how TEOTWAWKI Net works.
the arrows pointing to the ad-hoc cloud are as follows:
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Might have found a way to make an XO act as an AP
I did some digging around and asking on the olpc-devel irc channel and it looks like there is a driver and special "thin firmware" for the libertas chipset that supports AP mode. The guy that maintains the DebXO distro is having me test out a package that includes this new firmware. I will let you and him know about it as soon as I get a chance to test it. theres also instructions for getting the thin firmware working on the stock sugar, but it requires re-building the kernel with the correct options set.
(I will probably create a package for this if it all works out nicely under debian)
It will be so cool to be able to put an XO into AP mode. I've been making further improvements to the sync-up code and am working out some more bugs and timing issues. I also got my UNIX Network Programming 1st edition in the mail today as well.
What a wonderful history book to read from back in early 1990 when most of the world was not POSIX compliant, there were several competing network protocols with TCP/IP and some UNIX vendors were just getting around to getting ANSI compliant compilers (a lot of the examples are K&R style C but the sockets interface really hasn't changed much at all)
It deals a whole lot with interprocess communication and has some rally sophisticated examples and is very in depth. I know I'm going to learn a lot from it to make my project better.
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