Simple Shell Project

A simple Unix command line interpreter as a final first quarter project.

Objective.

Create a simple version of the Unix command line interpreter, with certain system calls allowed.

Description.

Is a command line interpreter that executes commands read from standard input.

Allowed and used system calls and functions.

• access (man 2 access)
• chdir (man 2 chdir)
• close (man 2 close)
• closedir (man 3 closedir)
• execve (man 2 execve)
• exit (man 3 exit)
• _exit (man 2 _exit)
• fflush (man 3 fflush)
• fork (man 2 fork)
• free (man 3 free)
• getcwd (man 3 getcwd)
• getline (man 3 getline)
• getpid (man 2 getpid)
• isatty (man 3 isatty)
• kill (man 2 kill)
• malloc (man 3 malloc)
• open (man 2 open)
• opendir (man 3 opendir)
• perror (man 3 perror)
• read (man 2 read)
• readdir (man 3 readdir)
• signal (man 2 signal)
• stat (__xstat) (man 2 stat)
• lstat (__lxstat) (man 2 lstat)
• fstat (__fxstat) (man 2 fstat)
• strtok (man 3 strtok)
• wait (man 2 wait)
• waitpid (man 2 waitpid)
• wait3 (man 2 wait3)
• wait4 (man 2 wait4)
• write (man 2 write)

Implemented functions

• _signal - Checks if a signal has been input.

• read_line - Read the entered arguments.

• tokenize - Parses the arguments into tokens.

• get_env - Getting the $PATH.

• check_path - Check if the file is in the path.

• execute - Check if the command entered is a built in or not.

• builtins - Default kernel commands.

• launch - Check if the command entered is in the $PATH.

• _fork - Create a new process to execute the command entered.

• _error - Print the standard error.

• _strncmp - Compare two strings in a specific range

• _strcat - Concatenates two strings.

• _strcmp - Compares two strings.

• _strcpy - Copies the string.

• _strlen - Counts string chars.

Compilation:

You can compile the project "printf" by do the following command:

   gcc -Wall -Werror -Wextra -pedantic *.c -o hsh 

Execution

    ./hsh

Examples:

Interactive mode:

$ ls
- - - - - - - - - - - - - - - - - - - - - - - - - - - - -
AUTHORS  _fork.c  auxiliar_functions.c  check_path.c
get_env.c  launch.c  man_1_simple_shell  simple_shell
README.md  _signal.c  builtins.c  execute.c  holberton.h
main.c  read_line.c  tokenize.c

---------------------------------------------------------

$ /bin/ls
- - - - - - - - - - - - - - - - - - - - - - - - - - - - -
AUTHORS  _fork.c  auxiliar_functions.c  check_path.c
get_env.c  launch.c  man_1_simple_shell  simple_shell
README.md  _signal.c  builtins.c  execute.c  holberton.h
main.c  read_line.c  tokenize.c

Non interactive mode:

echo "/bin/ls" | ./hsh
- - - - - - - - - - - - - - - - - - - - - - - - - - - - -
AUTHORS  _fork.c  auxiliar_functions.c  check_path.c
get_env.c  launch.c  man_1_simple_shell  simple_shell
README.md  _signal.c  builtins.c  execute.c  holberton.h
main.c  read_line.c  tokenize.c

Manual.

To enter the manual use the following code:

man -l man_1_simple_shell

Authors:

• Sergio Orejarena Rueda - GitHub / Twitter
• Jaime Arturo Blanco Gutiérrez - GitHub / Twitter

Flowchart:

Click to view the flowchart

Finished in 14 / 04 / 2021.