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The Adult Reference Library 1.a
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The Adult Reference Library Volume 1.a.iso
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sv.inf
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1993-02-12
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╔═════════════════════╗
║ ║
║ WHY IS SV NEEDED? ║
║ ║
╚═════════════════════╝
The EGA video display card can support screens showing 43 lines, instead of
the usual 25 lines that IBM PC compatibles have been using for years. The
more advanced VGA card (which is what most computers are now sold with) can
display up to 50 lines. (Actually, both cards can also use other modes, but
43- and 50-line modes are the only modes that are being widely supported.)
At the programming level, both modes are handled in a similar way. For this
reason, we refer to them here as a single mode (which we call "43/50 mode"),
even though they look different.
All of the programs in "The SEE Utilities" can detect if the user has set
his video card to 43/50 mode and behave appropriately. Of course, many
users have hesitated to lock themselves into one of these modes because
until recently, MS-DOS did not support it very well.
But now that MS-DOS works well with 43/50 mode, it is becoming popular.
Although the letters are somewhat harder to read than on a 25-line display,
you CAN get a lot more data on one screen. Once you get used to 43/50 mode,
you start avoiding programs that don't support it!
The SEE file viewer program does let the user toggle 43/50 mode on and off,
even if he started off in 25-line mode. This is handy for taking a quick
overview of a large collection of text. But as soon as the user exits the
SEE viewer, he is back in his original mode (usually 25-line mode). What we
need is a way to let the user set 43/50 mode PERMANENTLY, without having to
know any arcane DOS commands.
╔══════════════════╗
║ ║
║ THE SV COMMAND ║
║ ║
╚══════════════════╝
"SV" (short for "Set Video") is a small utility which can set your video
card into various modes. It can set 43/50 mode, for example. It can also
save the state of your video card, so you can restore it if a "badly
behaved" program leaves you in a mode you dislike (e.g. cursor off, red
border with yellow blinking characters on a blue background, 40 columns per
line, and so on!).
SV can be used in two ways. You can feed it parameters at the DOS command
line, or you can omit the parameters and use SV's simple menu interface.
(For use with "The SEE Utilities" -- in batch files -- you will usually use
it in the command-line mode, using the format: SV <mode-letter> OK)
╒═══════════════╕
│ QUICK-START │
╘═══════════════╛
You can learn most of what you need to know about SV by entering the
following command at the DOS prompt:
SV /?
This displays a quick summary of the command-line options.
╒═══════════════╕
│ SAMPLE CODE │
╘═══════════════╛
If you wish to provide support for various video modes when you use "The SEE
Utilities", you will find it helpful to see how we have done it (and borrow
the relevant lines of batch file code). The two files that you will want to
view are:
START.BAT The main batch file (hint: search for the label :SVSET)
SETVIDEO.MNU The GO-MENU definition used in the SVSET section of START.BAT
To view the file START.BAT, enter the following command at the DOS prompt:
SEE START.BAT
The SEE program can copy the section of the code you want into another file
(using the [C]opy command key). The lines that you require have been
clearly marked to indicate which ones you will need to copy.
We encourage you to borrow code from START.BAT and use SETVIDEO.MNU in your
own application, as long as you follow the distribution requirements
explained in the "INTRO" ("Introduction to the utilities") on the main START
menu.
╒═════════════════════╕
│ WHY ADD THE CODE? │
╘═════════════════════╛
It takes a bit of extra time to add support for SV, but it does provide the
user with a choice of the following four modes:
■ 25-line mode (monochrome)
■ 25-line mode (color)
■ 43/50 mode (monochrome)
■ 43/50 mode (color)
Many users will enjoy having a choice between 25-line and 43/50 modes and
will be appreciate being given this option.
Some users may find it difficult to see text if they do not have access to
monochrome mode. Although the programs in "The SEE Utilities" are easy to
read in a wide range of circumstances, occasionally people will hook up
color video display cards to monochrome monitors in such a way that some
lines of text show up as dark gray on light gray. If you are not sure who
is going to be using your product, you should consider adding in SetVideo
support.
╒════════════════╕
│ SAVE/RESTORE │
╘════════════════╛
Even if you don't use SV in your products, you should keep a copy handy,
somewhere in your DOS PATH. (For information about DOS PATH, see your DOS
manual) SV lets you save your video mode (when it is set up just the way
you like it) and restore it if it is set "wrong" -- usually because of a
badly-deigned program. You can save yourself a lot of annoying reboots by
using SV in this way.
╔══════════════════════════╗
║ ║
║ THE "MIDNIGHT" UTILITY ║
║ ║
╚══════════════════════════╝
Some authors like to equalize the DOS time-and-date stamp of all files in a
package just before they send out their finished product. This makes the
product look less haphazard when the user does a DOS DIR command. By
setting all files to the same time and date, it looks like your work came to
a definite and satisfying CONCLUSION, as opposed to simply grinding to a
halt for some reason!
The traditional way to set the file times is to alter the date with the DOS
TIME command, and then use a commonly available utility named TOUCH. This
is a bit awkward, and can even be disastrous if you forget to set your date
BACK after "touching" all the files!
The MIDNIGHT utility solves that problem. To set ALL files in your current
directory to midnight (00:00) of the current day, simply enter this command
at the DOS prompt:
MIDNIGHT
This will set the dates and times of files in the current directory. You
can, however, specify another directory as a parameter, as in this example:
MIDNIGHT C:\MYFILES