UNIX-SHELL

IIT Guwahati, India : CS-341 Assignment task - Make a UNIX Shell with some basic functionalities.

How to Run

$ gcc main.c
$ ./a.out

> <command-to-run>

Implemented Built-in Functions

> help

Displays the list of in-built functionalities.

> cd [path]

Changes the current working directory to the path specified.

> ls

Lists all the files/directories present in the current working directory.

> rm [-r] [-f] [-v] [file/dir]

Removes the specified files. Use the -r flag to remove a directory. -v flag displays the filename which is deleted.

> rmexcept [[file1] [file2]....]

Removes all the files in the current directory except the spefied files. NOTE:- It doesn't delete the directories in the current directory.

> history [n]

Displays the 'n' recent commands on the screen. If n is not spefied, then all the commands are displayed.

> issue n

Runs the n-th command again. Use the history command to check the number of the command.

> program_name [--tkill n]

This will run the specified program. It supports the redirection operators > output_file and < input_file. Note :- --tkill n is used to specify the time(in seconds) after which the program is terminated irrespective of whether the execution of child thread is completed or not.

> exit

Exits the terminal.

Special Note

1. Implemented all the features asked in the question statement.
2. Every command of the user is run as a separate thread forked by the main thread.
3. The memory used by history of commands is allocated dynamically in chunks of 10 commands. This is memory effecient and stores the complete history.
4. Each command given as input by the user also uses dynamic memory allocation in chunks of 1024 characters.
5. The code is completely modular. It is very effecient to read and understand with all the comments.

Bugs

There are no bugs.

Project Authors

Abhishek Goyal
Roll No - 150101002
IIT Guwahati (CSE)


Rohan Aggarwal
Roll No - 150101052
IIT Guwahati (CSE)


Roopansh Bansal
Roll No - 150101053
IIT Guwahati (CSE)