HASH -

Features

• Using commands with semicolons between them

• Handles input/output redirections

• Piping of one command into other works

• background and foreground activities -signal

• cd

• echo

• pwd

• ls

• history

• discover

• other system commands using execvp

• pinfo

• jobs

• fg

• bg

• sig

Files

main.c

clear display, show initial prompt and take input. it also catches signals.

cd.c

duplicates the cd command. can take a relative/absolute path as its argument.

echo.c

prints the argument followed by echo. handles tabs and extra spaces.

pwd.c

prints the current working directory

ls.c

implements the ls function of the linux terminal. handles flags and paths.

history.c

prints the last 10 executed commands. previous 20 commands saved in history.txt

discover.c

immitates the discover command as mentioned in the assignment assumes argument to the discover command to be given without quotes

syscommands

all other non user-defined commands are executed normally, using execvp. foreground and background processes

pinfo.c

prints the process related info of the shell

jobs.c

prints the background processes of the terminal

fg.c

changes the respective background command to foreground command

bg.c

changes the state of a stoped background process to running

tokenization

assumes no space after entered semi colon

headers.h

Contains all the required headers for all files

redirection

if > < input and output sources are mentioned, code executes it as per the given command

pipe

linux shell piping command is imitated also handles redirections with piping

signal_handling

ctrl Z ctrl C ctrl D