Notice

I am so sorry for not updating the blog in so long. But I will be able to soon. Unfortunately over the next week and a half, I will have to prepare for and take final semester exams at school. This will hamper my blogging and Harry's. I will have a couple of articles today, but probably not many until winter break. Just remember this when you see little updating on the blog. Hopefully I will find sometime later to keep posting.

Sincerely,
xatapu

The 100th Post....finally!

Finally, after a month of writing, I have hit 100 posts. I remember when I hit 20 posts sometime ago. I have covered C to commands to ports and even to desktop environments. I am also glad that I have had such a great coauthor as Harry is to contribute to the blog as well. He has added numerous useful reviews and bits of information. Insmod, still, however, has not added a single post since he joined me. I look forward to more writing and learning and (with hope) more development of my Unix skills. Maybe some inetd, httpd, and dhclient experiences in the future.................

xatapu

Command posts

For sometime I will be focusing on particular commands and utilities that can be used at the shell prompt. I have already began an article on mt, and plan to add ones on tcopy, rndctl, wsconsctl (I think that's the right spelling), df, gzip, cron, inetd, motd, rmail, etc. Mt and tcopy, specifically, are very interesting because they are tape drive commands. Anyway, posts on those commands and others will come up soon.

xatapu

Archives

If you are new to this blog, feel free to look through the archives. I have plenty of posts on every thing from Apple machines to vi to zsh (well, not yet zsh). Also please subscribe to the blog's feed. I think the one on the main page doesn't work, so go to http://feeds.feedburner.com/unixcomputing and subscribe there. I will also have that link up in the sidebar very soon.

Cool packages: bb

bb is a library for creating very advanced ASCII-based graphics. I learned this from insmod. I have also done a bit more research about it, and apparently looks like a demo of the AA library. AA is an "ASCII-art" library, and it is portable to many different platforms. I don't know much about it, so hopefully insmod will get a chance to put something up about it. For more information go to: http://aa-project.sourceforge.net/aalib/. This is the library's project page and has lots of info about it. It, of course, also provides a source download and describes the library.

News

Unfortunately, I wouldn't be able to post to the blog much this week. I will not have access to the Internet that often. I will try to continue next week.

The mt command

As I told you earlier, just yesterday I discovered the mt command. I know mv, but mt? Well, I then did a man on it. Mt........what the...........magnetic tape control?! I don't believe this! I can control a tape drive from a PC! I can send commands to it! The last time I did this was with a really old Texas Instruments TI-99/4A. Hmmm......I might explore this........

Anyway, let's get back to mt. Its syntax is mt [ -f tapename ] command [ count ]. Command and count will be explained shortly. The tape selecting option is -f, which selects the raw tape device. I believe /dev/rmt is the /dev folder for this. There are also a number of operands for mt. Here are some of them from http://bama.ua.edu/cgi-bin/man-cgi?mt+1, a online copy of the UNIX man pages:

count - The number of times that the requested operation is to be performed. By default, mt performs command once. Multiple operations of command may be performed by specifying count.

command - Available commands that can be sent to a magnetic tape drive. Only as many characters as are required to uniquely identify a command need be specified.

eof, weof - Write count EOF marks at the current position on the tape.

fsf - Forward space over count EOF marks. The tape is positioned on the first block of the file.

fsr - Forward space count records.

bsf - Back space over count EOF marks. The tape is positioned on the beginning-of-tape side of the EOF mark.

bsr - Back space count records.

nbsf - Back space count files. The tape is positioned on the first block of the file. This is equivalent to count+1. bsf's followed by one fsf.

asf - Absolute space to count file number. This is equivalent to a rewind followed by a fsf count.

(the next section is from http://www.computerhope.com/unix/umt.htm)

If count is specified with any of the following commands, the count is ignored and the command is performed only once.

eom - Space to the end of recorded media on the tape. This is useful for appending files onto previously written tapes.

rewind - Rewind the tape.

offline, rewoffl - Rewind the tape and, if appropriate, take the drive unit off-line by unloading the tape. It cycles through all four tapes.

status - Print status information about the tape unit.

retension - Rewind the cartridge tape completely, then wind it forward to the end of the reel and back to beginning-of-tape to smooth out tape tension.

reserve - Allow the tape drive to remain reserved after closing the device. The drive must then be explicitly released.

release - Re-establish the default behavior of releasing at close.

forcereserve - Break the reservation of the tape drive held by another host and then reserve the tape drive. This command can be executed only with super-user privileges.

erase - Erase the entire tape. Erasing a tape may take a long time depending on the device and/or tape. Refer to the device specific manual for time details.

Good, but a bit complicated and technical, as far as explanations. I guess an example (for those of you with tape drives out there) might be:

mt erase - erase the tape in the drive found at /dev/rmt0.

mt -f $RMT_NR eof 1 - Mark the end of the tape.

Very cool. Again, these are just probable examples of mt.

For more info, you can go to that man page I mentioned earlier. Another good place for learning about tapes and Unix is http://www.washington.edu/computing/unix/tapes.html. Also you can go to http://www.computerhope.com/unix/umt.htm for more info on use and syntax. That link also provides a link to a page on tcopy, a command I will be discussing soon. Enjoy!

Explorations in /bin and /sbin

Well, after being bored at the # prompt for sometime, I decided to look through the /bin and /sbin folders and find out what some of the stuff in those places do. Well, hmmm....theres mt, rndctl, wsconsctl, echo, rmail, and lots of other stuff. Let's man mt...........WHAT? magnetic tape control? Cool.......Hey, maybe I'll describe mt in the next command post.

My Palm III

All is well so far with my Palm III. I am getting used to Graffiti, and now I have a few games, a Logo interpreter, a Scheme compiler, and a Tcl console on my Palm. Pretty weird, huh? The games are Palm's own HardBall and SubHunt. I especially like its great battery life. Just two AAAs for weeks. I will have a photo of it next week, along, hopefully, with the PC photos I keep forgetting. I also plan to add a modem to it and...............login to a Unix server! Yes, I can do that, too! Unfortunately, I can't install Linux on it. I just need one of those little plastic sheets to keep my Palm from getting scratched..........

Cool packages: Gnuchess

Do you like to play chess? Do you want to learn to play chess? Are you sick of staring at the #, %, $, or > prompt? Then Gnuchess may be for you. This is Gnu's own version of chess. It is pretty simple, and can have both simple graphics and can be totally text based. I have not used this package much but I have gotten this through pkgsrc with several variations included. I plan to use this to play chess and as a break after I type. Overall, a nice, simple game package.

Spotlight: OpenBSD

Among the major branches of the BSD group of Unixes is OpenBSD, which, according to a April 2006 survey conducted by the BSD Certification Group among 4330 BSD users on various mailing lists, is the second most popular type of BSD (from OpenBSD Wikipedia article). I may, in fact, install this on my new laptop. But I am still thinking. After all, it did take me hours to finally install NetBSD, and that was NetBSD. Anyway. OpenBSD is highly portable, but not quite as portable as NetBSD. What OpenBSD is famous for is security. It is highly encryptable and has many features to help with securing servers and web pages. It is a simple and spartan but secure operating system. I will think about it........tell me what you think of it as well............
If you want to get it, there are a number of places to download it on iso images and through BitTorrent. Have fun and be safe. :)

Unix today: NetBSD update!

As of November 4, NetBSD 3.0.2 and 3.1 have been released. Earlier I told you about the beta version 3.1RC4. Now 3.1 was has been released as an update. For details on the new update, go to this webpage: http://www.netbsd.org/Releases/formal-3/NetBSD-3.1.html.

xatapu

Edition 5: Big Changes

Let's see. Already this blog has been updated for four weeks, with nearly 80 posts. We're now on the fifth, beginning this Wednesday, November 8. As for insmod, I am still waiting for a few columns from him. Harry has had some good ones, though. Although my blog has always changed rapidly, there are some large ones today. First, I will not be having particular 'themes' any more asthey are more constrained. Second, I am going to increase publishing and posting. Last week had the lowest on record, with only 11 posts. Third, I will try to dig a bit deeper and maybe get more "reader's responses" now.

Packages: Lynx

Okay. Picture this: You have just fallen into a dumpster near a university, when suddenly you feel a hard metal object slap you. You dig through the trash, and fined that is a DECstation from the early 1990s. Well, cool find, you think, but there's no internet with it! Wrong! With the help of Lynx, NetBSD/pmax, and perhaps a telnet connection, you can use the internet. Lynx itself is a text-based internet browser for Unix and many other operating systems. It is totally free and can also be downloaded through pkgsrc.

Palm devices

I got a Palm III about a year ago and didn't use it much then, but now I am getting back to it. I always had hated Grafitti, but then again I never practiced it. I know am starting to get Grafitti better. I also have found a few compilers (!) and interpreters for programming on it. They are LispMe, PtCon, and TinyLogo. The first and second are Lisp (Scheme) and Tcl interpreters. I also have put a few games on it. If only there was PalmBSD!

New digs: g++

Well, I haven't done much with C for some time now, so I guess I should be getting back to it. I have started again with base conversion now. I have experimented with an example interest-rate program which uses loops to print the interest on a sum over a period of time according to simple interest, or I=prt. I am now writing a base-conversion program and also plan to write a program for finding the viscosity of a fluid based on the fluid's shear stress and shear rate or velocity gradient as in a laminar shear experiment. Simple for now, but more will come.

Gnoppix

Hello again. I have searched for some time on Google and have found a distribution of Knoppix that uses GNOME. I think I might install this on a laptop if I find one. I understand from a reader's comment that GNOME is much cleaner than KDE.

Programming: gcc

Three reasons to install Linux or Unix on a PC: first, hear no Microsoft, smell no Microsoft, see no Microsoft; second, GNOME; third, gcc. Gcc is the GNU Compiler Collection, a universal Unix compiler that can compile just about everything from C to Fortran to Ada to Assembly to 00010111010100. It ships with most, if not all, Unix and Linux distros. I have been using to learn C, which is much easier under Unix. But you can still use it for many other things. In fact, I can compile machine-independent code with it. Later I will tell you more about personal experiences and programs I have compiled with gcc and g++.

Ports: NetBSD/hpcmips

Are you sick of Windows CE? Do you want a tiny Linux machine? Do you like rubbery, plasticky keyboards? Then this port is for you. NetBSD/hpcmips is a port of NetBSD for MIPS-based WinCE palmtops. About the only model which I saw it running on that is worth getting is the NEC MobilePro 790. But, still, it looks pretty cool. You get X with that little platter, too.

Unix today: SGI emerges from bankruptcy!

I know this is sort of old news, but on October 17th, Silicon Graphics emerged from Chapter 11 bankruptcy protection. The company's market share was being eaten by Apple and other companies that were strongly competing with SGI. SGI plans to end its mips line this December, and will use a new platform next year.