![]() |
4 years ago | |
---|---|---|
.. | ||
audit | ||
job-control | ||
scripting | ||
README.md | 4 years ago |
README.md
0-shell
Objective
The objective of this project is for you to create a simple shell.
Through the 0-shell
you will get to the core of the Unix
system and explore an important part of this system’s API which is the process creation and synchronization.
Executing a command inside a shell implies creating a new process, which execution and final state will be monitored by its parents processes. This set of functions will be the key to success for your project.
For this project you will only have to create a simple Unix shell
where you can run some of the most known commands. For this part of the project, no advanced functions, pipes or redirection will be asked, but you can add them if you like.
Instructions
- You must program a mini
Unix shell
, try to focus on something simple like BusyBox. - This interpreter must display at least a simple
$
and wait until you type a command line which will be validated by pressing enter. - The
$
will be shown again only once the command has been completely executed. - The command lines are simple, you will not have pipes, redirection or any other advanced functions.
- You must manage the errors, by displaying a message adapted to the error output.
- You must implement the following commands:
- echo
- cd
- ls
- pwd
- cat
- cp
- rm
- mv
- mkdir
- exit
- You must manage the program interruption
Ctrl + D
. - The project has to be written in a compiled language (like C, Rust, Go or other), interpreted languages (like Perl and others) are not allowed.
- The code must respect the good practices
This project will help you learn about:
- Shell
- Operating systems services
- Command-line interfaces
- Unix system
- Process creation and synchronization
- Commands syntax
- Scripting language
Bonus
You can also do more bonus features like:
- Manage the interruption
Ctrl + C
- Auto complete when you are writing
- Add piping
- Add redirection
- Have your path behind the
$
like (~/Desktop/0-shell $) - Add colors for the directories or errors
- Other advanced commands you may like.
Usage
student$ ./0-shell
$ cd dev
$ pwd
dev
$ ls -l
total 0
crw------- 1 root root 10, 58 fev 5 09:21 acpi_thermal_rel
crw-r--r-- 1 root root 10, 235 fev 5 09:21 autofs
drwxr-xr-x 2 root root 540 fev 5 09:21 block
crw------- 1 root root 10, 234 fev 5 09:21 btrfs-control
drwxr-xr-x 3 root root 60 fev 5 09:20 bus
drwxr-xr-x 2 root root 4400 fev 5 09:21 char
crw------- 1 root root 5, 1 fev 5 09:21 console
lrwxrwxrwx 1 root root 11 fev 5 09:20 core -> /proc/kcore
drwxr-xr-x 2 root root 60 fev 5 09:20 cpu
crw------- 1 root root 10, 59 fev 5 09:21 cpu_dma_latency
$ something
Command 'something' not found
$ echo "Hello There"
Hello There
$ exit
student$