adhithyaarun / Linux-Shell

A smaller scale simulation of a Linux Shell with a few added features, all written in C.

Linux Shell

How to use?

• To complile the program, run make
• To execute the executable thus created, run ./shell
• use the quit command to exit the shell
• You can run make clean on your terminal to remove executables generated by make

Commands:

Builtins:

• ls
  • ls -l
  • ls -a
  • ls -la
  • ls -al
• echo
• cd
  • cd <dir_path>
• pwd
• pinfo
  • pinfo <pid>
• clear
• clock -t <interval>
• remindme <duration> <message>
• quit
• setenv <var> <value>
• unsetenv <var>
• overkill
• jobs
• kjob <jobNumber> <signalNumber>
• fg <jobNumber>
• bg <jobNumber>

Other features:

• Redirection operators:
  • > output redirection (overwrite)
  • >> output redirection (append)
  • < input redirection
• | Piping operator
• Note: The piping operator can be used in combination with the redirection operators
• Ctrl + C kills the current foreground proccess.
• Ctrl + Z sends a foreground process to background and changes it's state to Stopped.
• All other terminal commands are excuted using fork.
• Processes can be run in foreground or background in this C - shell. To run in background, simply add an '&' to the end of a command.
  For example: gedit & will open gedit in the background, which allows us to continue using the shell.
• The user will be notified when a background process ends (including exit status).