DOS characters and commands

Does anyone know an easy way to remember what characters are legal/illeagal in DOS? Also, does anyone know how to remember which DOS commands are internal or external?

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RussS

Hmm - nothing comes to mind. I've been using DOS commands for years and I still occasionally use the wrong one.
The only commands I clutter my crain with are DIR and help /? ... lol

Webmaster

The way to remember them is 'simply' to use them... that's what you should be able to do when A+ certified, thats what your tested on. Just play around with the various commands. No need to try every option and parameter, just the obvious ones.

Internal command reside within command.com, external commands exists as a file on your hard drive. From the exam objectives, take the listed commands, and do a search on your hard disk for the file. (e.g. in \windows\command\ or \system32\ folder) to find out which are internal/external if your book doesn't list them. Common examples of internal commands are: cd, md, del and common examples of external commands are mem, fdisk, format

Webmaster

I just wanted to add, that although most of these commands originated in DOS, for the CompTIA exam and MS Windows these are command-line utilities

DOS is not longer part of the exam and most commands have changed a bit and have additional Windows specific options.

headcase

Internal - DOS commands that are built into the Operating System

External - Commands that must be executed from a file

One way to remember them, if you consider this a way, is that Internal commands are basic, while external commands are stored on disk

internal commands are located in the COMMAND.COM program, and are loaded into memory during the bootup process. For example, the DIR command is built into the OS and is a basic command.

external commands are stored on a disk. For example, to run FDISK (more advanced command) you would need a bootable floppy which contained the FDISK file.

Hope this helps