Quick starting guide

Dos9 is a open source command prompt meant to implement a superset of cmd.exe script language (known as batch by most devellopers). It is designed to be as simple to use as possible, reliable, portable and lightweight.

Getting started with Dos9

Firstly, if you have never used cmd or an equivalent interpreter before, you should definitely consider reading a tutorial about batch programming. On the other hand if you are already familiar with batch, just open Dos9 and start typing some commands ! Dos9 batch dialect is almost compatible with cmd.

If you use Dos9 on windows, the only file extension provided is .dos9 by default (to avoid trashing your OS with potential conflicts). However, calling a .bat or .cmd script from inside Dos9, leads them to get executed by Dos9.

Dos9 changes

Once installed, it is quite straightforward to play with Dos9, especially if you are quite familiar with cmd. However, there is a couple of thing out there you have to know about.

On one hand, there is a couple of differences between Dos9 and cmd :

The HELP system is different from the original cmd help system. On the first time you run the command, you need to genérate the whole documentation using:
```
  help /b
```
Once all the data has been generated you can use it as the help command, but beware, it's fairly improved.
There is a few FOR modifications:
- Empty line are processed by FOR /F. This behaviour can be disabled using:
```
    SETLOCAL EnableCmdlyCorrect
```
- Multiples lines can be used as input for FOR /F.
- Tokens can be specified in reverse order and can also overlap without bug.
Some undocumented but useful variables from cmd are still lacking (Though %=EXITCODEASCII% is now supported).
Dos9 has no inconsistencies with escaped characters with ^, it requires only one escape.
DIR /b does not automatically return absolute paths.
Support of START is a bit tricky under some platforms and some of the options or the whole command might not be provided depending on your system configuration if you use *nix.

On the other hand, Dos9 also provides you with with a bunch of extensions:

A full set of extensions to support floating points arithmetics through SET and IF:
- A new SET /a:f command to perform operations on floating point numbers.
- New comparisons like FEQ or FNEQ for the IF command to compare floating-point numbers.
The ground-breaking possibility to specify logical expressions using AND and OR and the new IF extensions, like in the following example:
```
  IF [ [ !ok! EQU 1 ] and [ defined file ] ] (
   :: some code 
  )
```
A module system allowing extension loading at run-time. This offer numbers of possibilities from graphical user interfaces to networking extensions. Currently, the only module provided is the BATBOX module.
To speed up parsing, Dos9 loads files entirely in memory at startup. If the file gets modified during its execution, it is reloaded and Dos9 restarts on the next line (counting lines from the begining). This can also be disabled using:
```
  SETLOCAL EnableCmdlyCorrect
```
As can be seen in the previous code, ::-style comments can be used inside blocks.
All the FOR modifications described above.
Enhanced GOTO and CALL that can use a file and a label at the same time and ignore errors:
```
  GOTO :mylabel myfile.bat /Q
  CALL /e :mylabel myfile
```
Extended HELP providing search capabilities and help in various formats including HTML.
The new command ALIAS allowing to set up simple and fast aliases for the commands:
```
  ALIAS dbs=dir /b /s
```

An extension to the FIND command to use simple regular expressions:

  echo match my regular expression | FIND /e "match * regular expression"

The FIND and MORE commands are provided as internal commands.
New internal commands XARGS and WC inspired from their *nix counterparts:
- XARGS runs a command taking command parameters on the standard input.
- WC counts line or words or bytes in a file.
```
    :: Count lines in subdirs 
    dir /s /b /a:-D . | xargs wc /l
```
New external command DUMP to dump hexadecimal code.
New SHIFT extensions and new %+ variable containing the remaining arguments.

Troubleshooting

Dos9 supports only two languages yet (french and english). If you cannot see the messages translated, please check the value of the LANG and LANGUAGE environment variables and set them appropriately.

If you have some questions about or need some help with Dos9, please feel free to join Dos9's official discord at: https://discord.gg/w4KtdCv

What's in this folder ?

There is a few interesting things in this directory that you might need:

BUILD.readme : A text file describing how to build dos9
WHATSNEW : A log of the changes made to Dos9
THANKS : A list of all the contributors to the project.
GUIDELINES : A text files giving guidelines on how to modify Dos9.
COPYING.* : The license of the project and of projects used by Dos9.

TSnake41/dos9-code

Quick starting guide

Getting started with Dos9

Dos9 changes

Troubleshooting

What's in this folder ?