OSN Assignment 2

OSN Assignment 2 made by Prakhar Jain (2022121008)

Instructions to Run

• Inside 2022121008_Assignment2 folder , run make and then ,./shell to start the shell

Prompt

• the shell starts with the prompt <USERNAME@HOSTNAME: CURRENT_WORKING_DIRECTORY>

Builtin Commands

• cd - changes the directoy . cd acommand also supports '.', '..', '-', '~' . works on both relative and absolute path

• pwd - prints the current working directory

• echo - prints the strings as it is after handling tabs and spaces

• ls - lists all the information of a file or files inside a directory also suppports -a (prints hidden files) flag and -l (prints information in long format) flag

• exit or quit - these commands will kill the terminal

Proesses

All other commands are treated as system commands

• background - commands ending with '&' are treated as background processes. After exiting the process name along with the pid is printed with status normally or abnormally.

• foreground - all other commands are treated as foreground commands. The time interval for which the command executes is also printed.

pinfo

• syntax - pinfo <pid> pid is optional

• If nothing is given as argument information about all child processes is given.

• If pid is given as argument then the information about the given process is printed.

discover

• Discover command searches for a file or a directory.

• -d - searches for all the directories.

• -f - Searches for all the files.

history

• History command prints the last 10 commands entered in the shell.