Used from the DOS prompt or in a batch file or in the CONFIG.SYS file to
set (or
display) whether or not DOS should check for a Ctrl + Break key
combination.
Used in the CONFIG.SYS file to set the number of disk buffers (number)
that will
be available for use during data input. Also used to set a value for the
number
of sectors to be read in advance (read-ahead) during data input
operations.
Like DEVICE, DEVICEHIGH is used in the CONFIG.SYS file to tell DOS which
device
driver software to use for devices; however, this option is used to
install the
device driver into the upper memory area.
Used in the CONFIG.SYS file to specify the memory location for DOS. It
is used
to load DOS into the upper memory area and to specify whether or not the
upper
memory blocks will be used.
Starts the Microsoft ScanDisk program which is a disk analysis and repair
tool
used to check a drive for errors and correct any problems that it finds.
XCOPY [d:][path]filename [d:][path][filename] [/A][/D:(date)]
[/E][/M][/P][/S][/V][/W][Y\-Y]
Copies directories, subdirectories, and files.
Syntax Notes
To be functional, each DOS command must be entered in a particular way:
this
command entry structure is known as the command's "syntax." The syntax
"notation" is a way to reproduce the command syntax in print.
For example, you can determine the items that are optional, by looking
for
information that is printed inside square brackets. The notation [d:],
for
example, indicates an optional drive designation. The command syntax, on
the
other hand, is how YOU enter the command to make it work.
Command Syntax Elements
1. Command Name
The DOS command name is the name you enter to start the DOS program (a
few of
the DOS commands can be entered using shortcut names). The DOS command
name is
always entered first. In this book, the command is usually printed in
uppercase
letters, but you can enter command names as either lowercase or uppercase
or a
mix of both.
2. Space
Always leave a space after the command name.
3. Drive Designation
The drive designation (abbreviated in this book as "d:") is an option for
many
DOS commands. However, some commands are not related to disk drives and
therefore do not require a drive designation. Whenever you enter a DOS
command
that deals with disk drives and you are already working in the drive in
question, you do not have to enter the drive designator. For example, if
you
are working in drive A (when the DOS prompt A> is showing at the left
side of
the screen) and you want to use the DIR command to display a directory
listing
of that same drive, you do not have to enter the drive designation. If
you do
not enter a drive designation, DOS always assumes you are referring to
the drive
you are currently working in (sometimes called the "default" drive).
4. A Colon
When referring to a drive in a DOS command, you must always follow the
drive
designator with a colon (:) (this is how DOS recognizes it as a drive
designation).
5. Pathname
A pathname (path) refers to the path you want DOS to follow in order to
act on
the DOS command. As described in Chapter 3, it indicates the path from
the
current directory or subdirectory to the files that are to be acted upon.
6. Filename
A filename is the name of a file stored on disk. As described in Chapter
1, a
filename can be of eight or fewer letters or other legal characters.
7. Filename Extension
A filename extension can follow the filename to further identify it. The
extension follows a period and can be of three or fewer characters. A
filename
extension is not required.
8. Switches
Characters shown in a command syntax that are represented by a letter or
number
and preceded by a forward slash (for example, "/P") are command options
(sometimes known as "switches"). Use of these options activate special
operations as part of a DOS command's functions.
9. Brackets
Items enclosed in square brackets are optional; in other words, the
command will
work in its basic form without entering the information contained inside
the
brackets.
10. Ellipses
Ellipses (...) indicate that an item in a command syntax can be repeated
as many
times as needed.
11. Vertical Bar
When items are separated by a vertical bar (|), it means that you enter
one of
the separated items. For example: ON | OFF means that you can enter
either ON
or OFF, but not both.