Simple_Shell

Introduction

Hey there! 👽
Thanks for checking out our Simple Shell Project. Here we have constructed our own Simple Shell that emulates the Bourne Again Shell.
Our Simple Shell is programmed to handle two built-in functions, which are env and exit. It is also programmed to be able to interperate commands in path with and without options such as ls or ls -a -l.
We appreicate your interest in this project and we would appreicate any feedback you could give us!

What is a shell?

A shell is a program that provides a command-line interface for users to interact with the computer's operating system. It allows users to execute commands and run programs by typing text commands.

Project Requirements

General

• Allowed editors: vi, vim, emacs
• All your files will be compiled on Ubuntu 20.04 LTS using gcc, using the option Wall -Werror -Wextra -pedantic -std=gnu89
• All your files should end with a new line
• A README.md file, at the root of the folder of the project is mandatory
• Your code should use the Betty style. It will be checked using betty-style.pl and betty-doc.pl
• Your shell should not have any memory leaks
• No more than 5 functions per file
• All your header files should be include guarded

Allowed Functions & System Calls

all functions from strings.h	perror (man 3 perror)
access (man 2 access)	printf (man 3 printf)
chdir (man 2 chdir)	fprintf (man 3 fprintf)
close (man 2 close)	vfprintf (man 3 vfprintf)
closedir (man 3 closedir)	sprintf (man 3 sprintf)
execve (man 2 execve)	putchar (man 3 putchar)
exit (man 3 exit)	read (man 2 read)
_exit (man 2 _exit)	readdir (man 3 readdir)
fflush (man 3 fflush)	signal (man 2 signal)
fork (man 2 fork)	stat (__xstat) (man 2 stat)
free (man 3 free)	lstat (__lxstat) (man 2 lstat)
getcwd (man 3 getcwd)	fstat (__fxstat) (man 2 fstat)
getline (man 3 getline)	strtok (man 3 strtok)
getpid (man 2 getpid)	wait (man 2 wait)
isatty (man 3 isatty)	waitpid (man 2 waitpid)
kill (man 2 kill)	wait3 (man 2 wait3)
malloc (man 3 malloc)	wait4 (man 2 wait4)
open (man 2 open)	write (man 2 write)
opendir (man 3 opendir)

How to download

• Go to this link

• Download files or copy the clone URL

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How to use program

Flowchart

Compiler

gcc -Wall -Werror -Wextra -pedantic -std=gnu89 *.c -o hsh

Testing

Your shell should work like this in interactive mode:

$ ./hsh
($) /bin/ls
hsh main.c shell.c
($)
($) exit
$

But also in non-interactive mode:

$ echo "/bin/ls" | ./hsh
hsh main.c shell.c test_ls_2
$
$ cat test_ls_2
/bin/ls
/bin/ls
$
$ cat test_ls_2 | ./hsh
hsh main.c shell.c test_ls_2
hsh main.c shell.c test_ls_2
$

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Program Contents

File	Prototype	Description
simple_shell.c	int main(int argc, char **argv, char **env)	Main function
clean_string.c	int cleanstr(char *line)	Prepares string for processing
tokenize.c	int tok_num(char *str, char *delims) char **tokstr(char *line, char *delims) int substrLen(char *str, char *delims)	Sections input for processing the called command
find_path.c	int find_path(char **path_array, char **args_array)	Directs operating system to called command
execute_program.c	int execute_program(char *op_path, char **string_array)	Executes the called command
free_helper.c	void free_string_array(char **array) void free_string(char *str) int free_the_mems(char **tokens_array, char **path_array)	Deallocates memory
main.h	Includes libraries, macros, and prototypes	Header file that provides futher instructions for program

Created by Michael Gans & Jess Dison