DASH

A basic terminal based shell written in C with I/O redirection and piping support.

Running:

• Go to the working directory
• Run make dash
• Execute ./dash
• Use exit to exit the shell

Features:

• Display - When you execute the code a shell prompt of <username@system_name:curr_dir> appears.

• Tilda(~) is replaced by current working directory and works for all commands listed below.

• Following Commands have been implemented seperately:

  • cd

  • pwd

  • echo

  • ls -[al] <Directory_Name>

  • pinfo Command

  • history

  • nightswatch

  • jobs

  • kjob

  • setenv/unsetenv

  • fg/bg

  • overkill

• Rest all commands are executed using execvp system call.

• Background Processes are also supported if ended with '&'.

• Exit status of finished background processes is displayed.

• Implemented piping and redirection

Files:

• main.c

  • main file which runs the program.

• input.c

  • getInput function takes the input and divides the input into semi-colon seperated commands.
  • getArgV function trims the command and divide it into necessary arguments.

• display.c

  • get the current username, hostname and working directory and display it.

• builtin.c

  • commands echo, cd, pwd are implemented.

• ls.c

  • ls along with its options is implemented.

• pinfo.c

  • pinfo

• execut.c

  • rest all commands are implemented.
  • checkfinish checks for all background processes that have stopped at start of loop.

• history.c

  • history

• nightswatch.c

  • nightswatch

• pipe_and_run.c

  • implemented piping and redirection