1. Make sure you are connected to the internet to be able to install the dependencies (using libreadline for I/O).

   NOTE: We have assumed debian based OS for installing dependencies in Makefile. To install dependencies on rpm based systems, invoke: $ sudo yum install libreadline-dev

2. run the following commands in order :

   $ make dependencies # (for debian based systems only)
   $ make all
   $ ./bin/shell
   

shell                - Project root     
|     
├── inc              - All .h files    
│   ├── handler.h    
│   ├── parse.h    
│   └── shell.h    
├── Makefile    
├── README.md    
└── src              - All .c files    
    ├── handler.c    - handles the parsed commands    
    ├── parse.c      - parses the commands passed     
    └── shell.c      - basic shell logic (taking input invoking parses and handler)  

make all # or link - to compile and link
make build - to build only
make clean - to delete all output files
make cleanall - to delete output files as well as TAGS and cscope files
make TAGS - to create emacs TAGS
make cscope - to create cscope files
make dependencies - to install dependencies (debian system)

1. basic shell commands : ls (with -all), cd, rm (with -r -v -f), exit

2. history n : Prints the most recent n commands issued by the numbers. If n is omitted, prints all commands issued by the user.

3. issue n : Issues the nth command in the history.

4. <program_name> : Creates a child process to run <program_name>, also supports the redirection operators > and < to redirect the input and ouput of the program to indicated files.

5. <program_name> m : creates a child process to execute program_name, aborts the process if it does not complete its operation in m seconds

6. rmexcept : removes all files except those in <list_of_files> from the current directory. NOTE: Our implementation does not support exception of file present in a subdirectory of current working directory.