simple_shell

Table of Contents

Overview Requirements

Overview

Simple Shell is a group project by Anne-Sophie Le Bloas and Dennis Pham. The goal is to create a simple and viable version of a Unix shell for Holberton School's first term final project.

Requirements

• Allowed editors: vi, vim, emacs
• Environment: Ubuntu 14.04 LTS
• Compiler: gcc 4.8.4 using the flags -Wall -Werror -Wextra and -pedantic
• Styling: Holberton School's Betty Style. It will be checked using betty-style.pl and betty-doc.pl
• No more than 5 functions per file
• All files should end with a new line
• All header files should be include guarded
• There is a list of allowed functions and system calls - System calls are only used when needed

Usage

The prompt #cisfun$ is displayed and waits for the user to type a command. The prompt will continue to be displayed everytime a command is executed. The shell uses the path environment and can also run commands with multiple arguments.

File List

AUTHORS

• lists all individuals having contributed content to the repository.

README.md

• Key information about the program

_getenv.c

• gets an environment variable

builtins.c

• Includes the following functions:
  • printenviron - print the current environment
  • __exit - exit a program
  • _siginterrupt - interrupt from keyboard

error_check.c

• prints error message contingent on invalid commands

exec_cmd.c

• executes tokenized commands

exec_path.c

• executes arguments concatenated to path directory

helpers.c

• Includes the following functions:
  • _strcmp - compres two strings
  • _strdup - duplicates a string
  • is_digit - checks if character is a digit.
  • _atoi - converts a string to an integer
  • _strlen - returns length of a string

holberton.h

• Header file

man_1_simple_shell

• Man page

path_concat.c

• concatenates two strings

print_unsigned_int.c

• prints a number to stderr

simple_shell.c

• main program

splitstring.c

• tokenize a string and puts tokens into array

str_concat.c

• concatenates two strings

tok_path.c

• stores each directory from path into an array

Installation

$ git clone git@github.com:dspham/simple_shell.git
$ cd simple_shell
$ gcc -Wall -Werror -Wextra -pedantic *.c -o hsh
$ ./hsh

• To exit the shell, the user can either type exit or ctrl + d

Interactive and non-interactive mode

In interactive mode, the user input is accepted from the command line. In non-interactive-mode, the user must first run the program:

$ ./hsh

Then a subshell opens, which accept the commands.

Builtins and commands

You can check the builtin commands in the man page: $ man ./man_1_simple_shell

Builtins:

• exit
• env

Examples

vagrant@vagrant-ubuntu-trusty-64:~/Holberton/simple_shell$ ./hsh
#cisfun$ w
 21:07:57 up 38 min,  1 user,  load average: 0.00, 0.01, 0.03
USER     TTY      FROM             LOGIN@   IDLE   JCPU   PCPU WHAT
vagrant  pts/0    10.0.2.2         20:31    7.00s  0.06s  0.00s w
#cisfun$ whoami
vagrant
#cisfun$ echo "hello world"
"hello world"
#cisfun$ pwd
/home/vagrant/Holberton/simple_shell
#cisfun$ uname
Linux
#cisfun$ bc
bc 1.06.95
Copyright 1991-1994, 1997, 1998, 2000, 2004, 2006 Free Software Foundation, Inc.
This is free software with ABSOLUTELY NO WARRANTY.
For details type `warranty'.
quit
#cisfun$ ls -lan
total 96
drwxrwxr-x 3 1000 1000  4096 Aug 29 20:38 .
drwxrwxr-x 3 1000 1000  4096 Aug 29 20:38 ..
drwxrwxr-x 8 1000 1000  4096 Aug 29 20:38 .git
-rw-rw-r-- 1 1000 1000   155 Aug 29 20:38 AUTHORS
-rw-rw-r-- 1 1000 1000  3896 Aug 29 20:38 README.md
-rw-rw-r-- 1 1000 1000   595 Aug 29 20:38 _getenv.c
-rw-rw-r-- 1 1000 1000   841 Aug 29 20:38 builtins.c
-rw-rw-r-- 1 1000 1000   571 Aug 29 20:38 error_check.c
-rw-rw-r-- 1 1000 1000   506 Aug 29 20:38 exec_cmd.c
-rw-rw-r-- 1 1000 1000  1240 Aug 29 20:38 exec_path.c
-rw-rw-r-- 1 1000 1000  1661 Aug 29 20:38 helpers.c
-rw-rw-r-- 1 1000 1000  1434 Aug 29 20:38 holberton.h
-rwxrwxr-x 1 1000 1000 18512 Aug 29 20:38 hsh
-rw-rw-r-- 1 1000 1000  1194 Aug 29 20:38 man_1_simple_shell
-rw-rw-r-- 1 1000 1000   673 Aug 29 20:38 path_concat.c
-rw-rw-r-- 1 1000 1000   625 Aug 29 20:38 print_unsigned_int.c
-rw-rw-r-- 1 1000 1000  1901 Aug 29 20:38 simple_shell.c
-rw-rw-r-- 1 1000 1000   953 Aug 29 20:38 splitstring.c
-rw-rw-r-- 1 1000 1000   646 Aug 29 20:38 str_concat.c
-rw-rw-r-- 1 1000 1000   817 Aug 29 20:38 tok_path.c
#cisfun$ exit
vagrant@vagrant-ubuntu-trusty-64:~/Holberton/simple_shell$

Collaborators

• Anne-Sophie Le Bloas - Github // Twitter
• Dennis Pham - Github // Twitter