Mysh

A simple shell implemented in C. Written as a part of Operating Systems coursework.

It should work in the similar manner as popular shells like bash, zsh etc. To run a command, type it into the shell and press Enter. All commands are terminated with newline character.

Features:

• Modular Code
  • One header file
  • Each functionality (command) is defined in different file.
• Color added for specific purposes.
• Proper error handling for each command.
• Proper handling of Ctrl+Z and Ctrl+C - similar to what happens in a normal terminal.
• Input/output redirection functionality.
• Command can be redirected using pipes as well as combination of pipes and I/O redirections.
• All basic features implemented.
  • Semicolon separated commands accepted
  • Builtin commmands like cd, echo, pwd.
  • Background and foreground processes.
  • Notification upon completion of finished background processes.
  • ls command implemented separately as required in the assignment with arguments -[al]
  • Exit and Quit commands for quitting the shell
• Non Standard "user-defined" commands:
  • "pinfo" : to display specific process related information.
  • "remindme" : a simple Personal Reminder.
  • "clock" : a command which displays dynamic date and time in your shell. There are two ways to run the clock, type clock --help to see.
  • setenv var [value] : create an environment variable if it does not exist.
  • unsetenv var : destroy the environment variable "var".
  • jobs : prints a list of all currently running jobs along with their pid, in particular, background jobs, in order of their creation along with their state.
  • kjob : takes the job id of a running job and sends a signal value to that process.
  • fg : brings a running or a stopped background job with given job number to foreground.
  • bg : changes a stopped background job to a running background job.
  • overkill : kills all background process at once.

Building and Running

cd linux-shell
make
./mysh