Hardware Reference
In-Depth Information
The amount of EMM is determined by the
Program Interchange File
(PIF).
This may either be one that is associated with an application or, if unspecified,
will be _default.pif. If the size specified in the PIF file is 0, EMM will be
disabled and the EMM line will be ignored.
A typical CONFIG.NT file (created using a simple text editor) might be as
follows:
dos=high, umb
(load DOS into high memory)
device=%SystemRoot%
\
system32
\
himem.sys
(use the himem memory manager)
files=40
(allow for 40 open files)
Using
AUTOEXEC.BAT
The AUTOEXEC.BAT file allows you to automatically execute a series of pro-
grams and DOS utilities to add further functionality to a system when the system
is initialized. AUTOEXEC.BAT normally contains a sequence of DOS com-
mands but in addition it can also contain the name of an application or shell
that will be launched automatically when the system is booted. This is a useful
facility if you always use the same shell or application whenever you power-up
your system, or if you wish to protect the end-user from the need to remember
rudimentary DOS commands (such as
MD, CD, XCOPY,
etc.).
AUTOEXEC.BAT is typically used to:
1
set up the system prompt (see page 118);
2
define the path for directory searches (using SET PATH, see page 118);
3
execute certain DOS utilities (e.g. SHARE);
4
load a mouse driver (e.g. MOUSE.COM);
5
change
directories
(e.g.
from
the
root
directory
to
a
'working'
directory);
6
launch an application or menu program (e.g. MENU.BAT).
It is important to note that Windows and some DOS programs have their
own built-in mouse drivers and can thus communicate directly with the mouse.
However, if you regularly use a mouse with DOS applications, you will prob-
ably wish to include reference to your mouse driver within the AUTOEXEC.
BAT file.
If you are operating from within a DOS environment and you do decide to
experiment with your CONFIG.SYS and AUTOEXEC.BAT files, it is essential
to make sure that you keep back-up copies of your original files (CONFIG.BAK,
CONFIG.OLD, etc.). If you are experiencing problems with memory limitations
you can use the
MEM
command with the
PROGRAM
,
DEBUG
,or
/CLASSIFY
switches
to see the effect of changes made to DOS drivers and memory managers.
A typical AUTOEXEC.BAT file (once again created using nothing more than
a simple text editor) might be as follows:
PROMPT $P$G
(prompt with directory path)
LOADHIGH=C:
\
DOS
\
SHARE.EXE
(permits file sharing and locking)
SET COMSPEC=C:
\
DOS
\
COMMAND.COM
(specify the location of the command interpreter)
SET PATH=C:
\
DOS;C:
\
UTILITY;C:
\
TOOLS
(search DOS, UTILITY, and APPS directories)
MENU.BAT
(launch the menu batch file)
