Simple-shell-os

This project is a simple job scheduler implemented in C. It supports adding, scheduling, and executing jobs with specific commands. The job scheduler is capable of handling foreground and background jobs, with a focus on round-robin scheduling.

Features

Command Line Interface: Interactive prompt to enter commands.
Builtin Commands: Support for commands like quit, jobs, bg, fg, addjob, schedule, and help.
Job Management: Add and schedule jobs with specified burst times and arrival times.
Round-Robin Scheduling: Jobs are executed based on a round-robin scheduling algorithm.
System Commands: Execute system commands like ls and run C programs.

Getting Started

Prerequisites

GCC compiler
Unix-like operating system (Linux, macOS, etc.)
WSL

If folder is stored in c drive

To mount drive, use the following command:

sudo mkdir /mnt/c

sudo mount -t drvfs C: /mnt/c

Now, get that directory:

cd /mnt/c/shell

Compilation

To compile the project, use the following command:

sudo gcc shell.c -o shell

Running

Run the compiled program:

sudo ./shell

You will be presented with a prompt vansh> where you can enter commands.

Usage

Builtin Commands

quit: Exit the shell.
jobs: Display the total number of jobs.
bg: Display the number of background jobs.
fg: Display the number of foreground jobs.
addjob <name> <burst_time> <arrival_time>: Add a new job.
schedule: Schedule and execute jobs in Round Robin manner.
help: Display the help message with available commands.
ls: Show files in the current directory.
run <filename>: Compile and run a C file.

Examples

Adding a Job:
```
vansh> addjob job1 5 0
```

Scheduling Jobs:
```
vansh> schedule
```

Running a System Command:
```
vansh> ls
```

Compiling and Running a C Program:
```
vansh> run program.c
```

Showing What all commands are there:
```
vansh> help
```

Displaying number of jobs:
```
vansh> jobs
```

For going back to the terminal
```
vansh> quit
```

Error Handling

The shell provides feedback for incorrect usage or errors encountered during command execution. For example:

Trying to add a job with incorrect arguments will display a usage message.
Exceeding the maximum number of jobs will display an error message.

Code Structure

main.c: Contains the main function, command parsing, and job scheduling logic.
job.c: Manages job structures and scheduling functions.
command.c: Handles command parsing and execution.

Future Enhancements

Improve job scheduling algorithm to support more complex scenarios.
Add support for job priorities.
Enhance command parsing to handle more complex command structures.

License

This project is licensed under the MIT License.

Author

Vansh - GitHub

vansh-seth/Simple-shell-os