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This arrangement again requires a DOS machine with a speech synthesizer and a terminal emulator program. However, instead of dialing up a remote computer, it is used as a terminal to a local computer running Linux. To get to this point, you need to install Linux on a machine. You may be able to prevail on a knowledgeable friend to help you with this. However, it is also possible to install it yourself with speech feedback for almost the whole procedure.
First, some background. Even the simplest Unix system requires a program called the kernel and a root file system. The kernel has all the device drivers and resource management functions. One normally thinks of a "file system" as residing on a hard disk or floppy disk, but during an installation it is usually in ram. Linux is normally installed by writing a kernel image to a floppy disk, called the "boot floppy", configuring it to reserve a section of RAM for a ramdisk, then filling that ramdisk with data from a second floppy disk, called the "root floppy". As soon as both floppies have been read in, the user can log in as "root" and complete the installation. The sighted user logs in on the "system console", that is, the computer's own keyboard and video display. However, remember that Unix has been a multiprocessing operating system from the very beginning. Even this very primitive Unix system, running out of a small ramdisk, also supports logins from a terminal connected to a serial port. This is what a blind user can use.
To connect the two computers, you can use a "null modem", a serial cable that connects ground to ground, and transmit on each end to receive on the other. The cable that comes with the DOS application LapLink will work fine. It is particularly handy, in fact, because it has both a 9 pin and a 25 pin connector on each end. If you want to check a cable or have one made, here are the required connections:
For two 9 pin connectors, connect pin 2 (receive data) to pin 3, pin 3 (transmit data) to pin 2, and pin 5 (signal ground) to pin 5.
For two 25 pin connectors, connect pin 2 (receive data) to pin 3, pin 3 (transmit data) to pin 2, and pin 7 (signal ground) to pin 7.
For a 9 pin connector (first) to a 25 pin connector (second), connect pin 2 (receive data) to pin 2 (transmit data), pin 3 (transmit data) to pin 3 (receive data), and pin 5 (signal ground) to pin 7 (signal ground).
You may have noted that I have included no connections for the
"handshaking" signals. During login, the serial port is handled by
Consult the documentation on your CDROM, or downloaded from an FTP site, and choose a boot disk with the proper kernel features for your hardware (IDE or SCSI, CDROM driver, etc.). I have the InfoMagic September 1996 "Developer's Resource" set of six CDROMs. Slackware 3.1 is on disk 1 of that set, mostly in the two directories slackwar and slakware. (Note the difference in spelling. You will access them in alphabetical order: first slackwar, then slakware.)
Documentation on the boot floppies is in \bootdsks.144\which.one. A copy of the DOS program for writing boot images to a floppy, rawrite.exe, is in the same directory. Assuming the CDROM is the M drive under DOS, one might use these commands to write to a floppy disk in the A drive:
Similarly, to write the "text" root disk:
If you install from floppies, you should also copy the Emacspeak package onto a floppy with a command like this:
For the actual installation, proceed as follows: Use the null modem to connect the computer running DOS and equipped with speech output (which I will call the "DOS machine") to the computer into which you want to install Linux (the "Linux machine").
Boot the DOS machine, and start your terminal emulation program. Set it up for 9600 baud, no parity, eight data bits, 1 stop bit.
On the Linux machine, insert the "boot" disk and boot (power up, cntl-alt-del, or hit the reset switch). It should read the disk for five seconds or so, beep, and stop with the following text:
(Note: in the following, the large blocks of text quoted from the installation disks are preceded by "-- begin quote" and followed by "-- end quote". To skip to the end of a quote, you may search for two dashes starting in the first column. I have word wrapped some sections to limit the line lengths.)
-- begin quote
-- end quote
I have almost always been able to just hit "enter" at this point.
After your entry, the Linux machine should read the floppy for another twenty seconds or so, then boot the kernel. The first thing it prints is "Loading ramdisk...", which is somewhat misleading. In this case, "ramdisk" is actually the name of the kernel configuration.
Each device driver in the kernel displays a line or two. The particular disk I'm using (the "bare.i" bootdisk) displays more than one screen's worth. It is possible to type shift-page up to scroll the text back. On my machine, the boot messages are as follows:
-- begin quote
-- end quote
Some messages will of course be different on a machine with different hardware. Now, insert the "text" rootdisk and press ENTER. After it is read, the following is displayed on the console:
-- begin quote
-- end quote
The program that prints the login prompt is called
I will repeat that with explanations of what is going on.
First, type "root" and a single carriage return
to log in (no password is needed). Next, you need to append one line
Finish each line with the "enter" key. Then type a control-D, which
signals end of file to a Unix program. (Note: In the second line, the
next to last character is an upper case "S". Everything else is in
lower case.) This adds a line to the configuration file
of the program
If you don't get the Slackware installation disk prompt, try the following:
Once you get the above prompt on the DOS machine, you may type
The installation script will offer to prepare a boot floppy. You
should do this, since it is the most foolproof way to boot Linux. You
will probably also want to install
After the Slackware setup script finishes the main installation, it will tell you to restart by pressing cntl-alt-del. Before doing that, you should install emacspeak. It can be found with the other "contributed" software. In the InfoMagic set, it is in slackwar/contrib. Assuming you are installing Linux directly from a CDROM, the setup script will mount the CDROM under /CDROM, and you may install emacspeak with the following command:
If you install from floppies, insert the floppy you made earlier and type this:
You should not install the package directly off the floppy disk, because the DOS filesystem will not allow the full filename, so the installpkg program will think the package name is "emacspea" and will store its records under that name.
If you have a DoubleTalk or LiteTalk speech synthesizer, you should also install the emacspeak-dt package.
Reboot the Linux machine with the new boot floppy, with the DOS machine still connected. You should get a login prompt on the DOS machine. Celebrate! After getting this system working, you need to learn emacs (third option) and Unix system administration.
Mostly you will learn system administration as the need arises. First adding a user (yourself), then installing programs, and so forth. The exception to this is making backups, which you should learn before you need them.
Among the many programs you will need to learn are these:
Here are some programs you may want to install:
Here are some Web pages related to Unix system administration:
There is a Unix system administration tutorial at http://www.iem.ac.ru/sysadm.html
UnixWorld Online Magazine Home Page http://www.wcmh.com/uworld/
Internet Essentials for UNIX System Administrators Tutorial http://www.greatcircle.com/tutorials/ieusa.html
Pointers to Unix goodies available on the Internet http://www.ensta.fr/internet/unix/
Pointers to Unix system administration "goodies" available on the Internet http://www.ensta.fr/internet/unix/sys_admin/
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