Mini Shell

A Unix shell implementation written in C++ from scratch for learning purposes. Supports pipelines, I/O redirection, job control, and signal handling.

Requirements

• Linux or macOS
• g++ with C++17 support
• make

Build

git clone https://github.com/ValijonSharifjon/mini-shell.git
cd mini-shell
make

Run

./myshell

To exit:

myshell>> exit

Features

Basic commands

Any command available on your system works:

myshell>> ls
myshell>> echo hello world
myshell>> cat file.txt

Built-in commands

Command	Description
cd <dir>	Change directory
pwd	Print current directory
jobs	List background jobs
fg %<n>	Bring job to foreground
bg %<n>	Resume job in background
exit	Exit the shell

Pipelines

Chain commands together with |:

myshell>> ls | grep .cpp
myshell>> cat file.txt | sort | uniq
myshell>> ps aux | grep sleep

I/O Redirection

myshell>> echo hello > output.txt       # write stdout to file
myshell>> cat < input.txt               # read stdin from file
myshell>> ls 2> errors.txt             # write stderr to file
myshell>> ls 2>&1                      # redirect stderr to stdout
myshell>> ls | grep txt > result.txt   # pipe and redirect together

Background processes

Run a command in the background with &:

myshell>> sleep 100 &
[1] 12345
myshell>>                  # prompt returns immediately

Job control

myshell>> sleep 100 &
[1] 12345
myshell>> sleep 200 &
[2] 12346
myshell>> jobs
[1]  Running    sleep 100
[2]  Running    sleep 200
myshell>> fg %1            # bring sleep 100 to foreground
myshell>> bg %1            # resume in background after Ctrl+Z

Signals

Shortcut	Action
Ctrl+C	Kill foreground process (shell stays alive)
Ctrl+Z	Suspend foreground process
Ctrl+\	Ignored

Make commands

Command	Description
make	Build the project
make test	Run tests
make format	Format code
make clean	Remove binary