DOS

ESSENTIAL Command Line
DOS IS DEAD - LONG LIVE THE COMMAND LINE!

Welcome to the wonderful world of DOS. In DOS's world we don't shove our operating system around like we do with our mouse & Windows. No, in DOS we use our keyboard and "chat" with it.

Imagine a conversation with a very gifted three-year old. If we want to get anywhere, we better learn to communicate with it using a language that it understands.

But if you can stick with it, learn to enjoy it, don't get too impatient with it, DOS can be a very important troubleshooting ally. And who knows, maybe you can join the club of DOS super-heros and save the world from getting too GUI...

Getting About At the Command Line

Basics

Command line Commands are issued from the command prompt. They consist of "reserved words" (the actual command name) plus any parameters or switches. We may type the commands, parameters & switches in UPPER, lower or MiXeD cases. Although not always mandatory, it is best to separate commands, parameters & switches with spaces.

Command: These are the actual "reserved words" – words that the command interperater used in its lexicon. Commands may be internal (they are placed into memory when the file COMMAND.COM is loaded), or external (they are actual "files" on the disk).

Parameter: Information typed after a command that specifies what the command should act on. This gives the command some data to work with, sort of like an "argument" in an Excel function.

Switch: Generally a switch consists of a forward slash (/) followed by one of more numbers or letters. A switch modifies the way DOS carries out a command.

Example:	DIR	C:\Windows	/w
In nerd:	command	parameter	switch
In English	do this	to this	in this manner

A VERY helpful switch in later versions of the command line is the /? switch! This switch tells you which switches and kinds of parameters can be used with the command.

If the command line doesn’t understand what you want it to do, it replies with: "Bad command or filename…" OR " '...' is not recognized as an internal or external command, operable program or batch file."

DCommand prompt:

The command interpreter can let us know what drive & directory we are in by showing this current "path" in the prompt. If you are on the C: drive and in the Windows directory the prompt might look like this: C:\Windows>

If we move back to the directory that contains the Windows directory (called the root directory) the prompt would look like this: C:\>

Changing drives:
Oftentimes we need to tell the command interpreter to "look at" a different drive (or device). To change drives, type in the letter of the drive you want to change to, a colon, and press the enter key. Do this with a formatted disk in floppy A:

Type a: <press the enter key>

This would tell the system to change to the floppy drive A. The prompt would look like this: A:\> To change back to C: type: c: <press the enter key>

DOSKEY

Easy access to previously issued command line commands! Use the up and down arrow keys. This feature is built into the command interpreter in Win2K and up.

Or you can usually use F3 to access the very last command…

File and directory names - Very A+

Legal Characters in Filename:

A - Z 0 - 9 $ # & @ ! ( ) - { } ' ` _ ~

Illegal:
| < > \ ^ + = ? / [ ] " ; : , * plus control characters and the space

WILDCARDS

Many commands associated with file handling (eg. ATTRIB, COPY, DEL, DELTREE, etc.) accept the use of the "wildcards" (* and ?). In general terms, * refers to multiple characters and ? refers to a single character in a file or directory name.

Wildcard	Typical interpretation
*.*	All files with all extensions.
**letter.***	All files with "letter" anywhere in its name.
*smith.*	All files with names ending with "smith" (or "Smith")
Test?.txt	All files named "test" + one character and with txt extensions (eg test1.txt, but not test-a.txt nor test.txt)

SHORTCUTS

A number of commands recognize certain shortcuts when navigating between directories. The best known of these are:

.	to refer to the current directory
..	to refer to the parent directory
\	to refer to the root directory of the current drive.
Drive:	to refer to the current directory on drive

It is very A+ to know how to get to a session in the various flavors of Windows:

Win95 and Win98 – Start / Programs / MS DOS Prompt

Windows ME, NT, 2K and XP – Start / Programs / Accessories / Command Prompt

In any of them – Start / Run / <type> command

In NT, 2K or XP – Start / Run / <type> cmd (true 32-bit DOS subsystem)

DOS - Disk Operating System

MSDOS is a single user, single tasking, 16-bit operating system.

Single user means only one person uses the computer at a time.

Single tasking means that it essentially only runs one application program at a time, and has no inherent support for running more than one application program simultaneously.

16-bit means the OS can deal with data in 16-bit chunks.

Standalone Versions 1.00 - 6.22

Version 7x comes (free) with Windows 9x

DOS Boot process - (post POST & bootstrap loader) - Very A+

IO.SYS - a DOS version of BIOS-type procedures. It has default device drivers for things like:

Console display and keyboard
Parallel communications - printer
Serial communications – modems, mice and printers

MSDOS.SYS - disk and device handling programs (the kernel of DOS): In DOS versions < 7.0 it supports things like:

File management
Memory management below 1MB
Execution of other programs

CONFIG.SYS (optional - configures drivers that IO.SYS leaves out)

User can change
Configures hardware
Memory management drivers go here

COMMAND.COM - internal DOS commands

AUTOEXEC.BAT (optional - sets up the DOS environment)

User can change
Configures environment
TSR (terminate and stay resident)

Fun With the Command Line – This assumes DOS Version 7

The DIR command and Help

C:>dir /? <enter>

Nothin’ but DIR – getting acquainted with DOS syntax

Change the Directory display

Normal	DIR
Help	DIR /?
Screen-at-a-time	DIR /P
Wide display – less data	DIR /W
Both	DIR /W /P

A personal favorite

Show current directory AND subdirectories

Can be combined with file names to FIND specific files.

DIR /S

DIR ufoundme.txt /S

Change Sort Order

Normal	DIR
By size Small to large Large to small	DIR /OS DIR /O-S
By date	DIR /OD

By date with a pause True geek way	DIR /OD /P <OR> DIR /OD \| MORE

Show files with specific attributes

Normal	DIR
Everything!	DIR /A
Just hidden	DIR /AH (Or /AA /AR /AS /AD)
Hidden and system	DIR /AHS
Hidden NOT system	DIR /AH-S

Now that we have mastered how DOS works using the DIR command, let’s move on to some other commands…

Using FORMAT and SYS

Format a DISK (or volume)	FORMAT C: DIR C: /A
Format a DISK real fast… Note that you CANNOT quick format right after you have modified partitions with FDISK, or on a disk that has not been formatted with DOS already.	FORMAT C: /Q
Format a DISK and make it bootable	FORMAT C: /S DIR C: /A
Format a DISK and give it a name	FORMAT C: /V:TECH
Copy system files only	SYS C:
Do it all… Only for the brave…a format with no questions asked. May use /s	FORMAT C: /S /V:TECH /Q FORMAT C: /AUTOTEST

Using PATH'rudy' is not recognized as an internal or external command,
operable program or batch file.

The path command sets the PATH that DOS will search through for executable files. By default DOS checks ONLY the current directory and gives up!

In your work in this class, if you see this message "Bad command or filename" when issuing a DOS command, suspect a PATH problem.

The PATH can be set/modified in the AUTOEXEC.BAT file or from the command prompt

See current PATH	PATH
Test… Now fix'rudy' is not recognized as an internal or external command, operable program or batch file.	MEM SET PATH=\command
Give it a test	MEM

Using ATTRIB

View attributes of files in current directory Getting too much info?	ATTRIB ATTRIB \| MORE
Hide a file	ATTRIB 1.txt +H
Unhide a file	ATTRIB 1.txt -H
Unhide a system file: Try this first – Here is the way	ATTRIB IO.SYS -H ATTRIB IO.SYS -S ATTRIB IO.SYS -H -S
DO NOT (unless you mean it)	ATTRIB +H <note no file name>

Using VER

View DOS/Windows version

VER

Using Copy / Move

Syntax	COPY source destination
Normal	COPY A:\1.txt A:\stuff Or, to be less explicit… COPY 1.txt \stuff
Copy and rename	COPY 2.txt \stuff\newname.txt
Copy with wildcard	COPY *.bak C:\
Copy from the console to a file. A walk on the wild side…	COPY CON myfile.txt <enter> Some text goes here… <press F6> ^z

Using TYPE

View the contents of a text file

TYPE myfile.txt
TYPE COMMAND.COM

Using EDIT

Edit a text file	EDIT
Run EDIT with a file	EDIT myfile.txt EDIT COMMAND.COM

Using XCOPY

If you want to copy whole directories of stuff then XCOPY is your tool. Go into your "STUFF" directory	XCOPY source destination
Will copy stuff directory to root Without explicitly specifying the \stuff directory, XCOPY will copy the contents of *stuff* to the root.	XCOPY inside \inside /e "Does inside represent a file name or directory name on the target? Answer "D""
If you want to copy the Win98 directory from the CD in D: to the hard drive at C:	XCOPY D:\WIN98 C:\WIN98
If you want to take *everything* and you are using DOS7 (in a session) then:	XCOPY source destination /R /I /C /H /K /E /Y

Potpourri - Rename / Delete files / Make and Remove directories / move around

Change directory	CD stuff CD .. CD \stuff\inside CD ..
Rename	REN 6.txt 6.bak RENAME 6.bak 6.txt
Delete	DEL \stuff\newname.txt ERASE \stuff\1.txt
Make a directory	MD APLUS MKDIR BPLUS MD TESTME <Now copy all .bak files to this directory>
Remove an empty Directory	RD APLUS RMDIR BPLUS RD TESTME
Remove a directory and EVERYTHING inside it	DELTREE TESTME

Using SCANDISK and DEFRAG

Scan a disk for errors (done before a defrag) Crosslinked = a cluster assigned to two different files Lost clusters = a file whose clusters aren’t associated with it	SCANDISK
Or do it the old way… Check and display status of the disk. Will create those .CHK files in your root (done before a defrag) Use SCANDISK when available!	CHKDSK [/F to fix]

Using SETVER – fixes Incorrect DOS version message

SETVER is installed as the first line of config.sys

DEVICE=\SETVER.EXE

You may view the current SETVER table

Try to run the DOS 6.20 TREE command that is in your COMMAND directory. You should get, "Incorrect DOS Version"

Enter a program into the SETVER table. You may add the program to the SETVER table like this:
SETVER PROGNAME.ext n.nn

You will need to reboot. Should work like a champ now. How do you like it?

SETVER

TREE

SETVER TREE.COM 6.20

TREE

EOE – End of exercise

IT’S ALL ABOUT YOUR MEMORY! – Probably fallen off the edge of A+

MS-DOS And Memory
DOS can only "see" the first megabyte - 1024K - of RAM. This is the memory that DOS can directly manage without the use of additional memory managers.

MEMORY CLASSIFICATIONS

Conventional Memory
The first 640K memory storage locations (bytes) of your PC. Used traditionally for data and programs.

Upper Memory - UMA
The next 384K memory storage locations (bytes) of your PC. Used traditionally by hardware / BIOS.

Expanded Memory - EMS
A technique for increasing memory in DOS PC’s. It allows DOS to work with up to 32MB of extra memory by switching segments of EMS memory into upper memory

Extended Memory - XMS
In Intel 286’s and up, it is standard memory above one megabyte. Extended memory is used directly by Windows.

High Memory - HMAThe first 64K of memory from 1024K to 1088K which can be accessed by DOS. It is managed by the HIMEM driver.

DOS MEMORY Map
Anything above 1MB	Extended (XMS)	< up tp 32MB Expanded (EMS)
1st 64K after 1MB	High
640K-1024K	Upper
0-640K - 1	Conventional

UPPER MEMORY Map
640K - 1000K	BIOS ROM	F0000-FFFFF
	Network Card ROM EMS Page Frame	D8000-DF000 D0000-DFFFF
	VGA Video ROM	C0000-CFFFF
	Video RAM	A0000-BFFFF

Using MS-DOS Memory Managers – Very A+

To use your computer’s extended memory, expanded memory, high memory or upper memory area, your CONFIG.SYS file must contain a command that loads a memory manager. MS-DOS includes the following memory managers:

HIMEM.sys, which provides access to extended memory and high memory

EMM386.exe, which provides access to the upper memory area and uses extended memory to simulate expanded memory.

MS-DOS does not include an expanded-memory manager for physical expanded memory, since each expanded-memory board requires it’s own memory manager.

More exercising…

Modifying Boot Parameters

I will explain what each line does. Add an extra line under each line for your comments. Begin each new comment line with a ; or a REM

EDIT CONFIG.SYS

;edited by rudy
device=himem.sys
device=emm386.exe noems
dos=umb,high
lastdrive=m
files=15
device=oakcdrom.sys /d:TEACHME

EDIT AUTOEXEC.BAT

REM edited by rudy
@echo off
set path=\command
doskey
mscdex /d:TEACHME
smartdrv

Using MEM

Shows DOS memory organization	MEM
Classify memory Pause the display	MEM /C MEM /C /P
Really, really classify memory…	MEM /D /P

Modify your config and autoexec files: Change device to devicehigh Change doskey to lh doskey Change mscdex to lh mscdex Note that by default, SMARTDRV will move itself to upper memory if available.	MEM /C /P

DOS < 7 also provides us with a tool to view memory and other resources. This tool is called Microsoft Diagnostics (MSD).

XP Command Line Tools

rd /s (instead of deltree)

chkdsk /f

diskpart
diskpart>
select disk 0
detail disk
list disk
list partition
list volume

tasklist
tasklist /svc
taskkill

sc queryex
sc stop themes
sc start themes
sc queryex | findstr /i “themes”

Windows Management Instrumentation Console
wmic /?
wmic cpu > c.txt
notepad c.txt

Try some of your own… BIOS, BOOTCONFIG, DESKTOP

wmic process WHERE (Description="explorer.exe")
wmic qfe list full | more

WMIC /NAMESPACE:\\root\wmi PATH MSStorageDriver_FailurePredictStatus

netsh diag show test

netsh diag gui

If you have downloaded the XP support tools then:

netdiag /v > c.txt
notepad c.txt

Edited (2007)