holbertonschool-simple_shell

holbertonschool-simple_shell this is a team project on SIMPLE-SHELL

Content

• MAN_PAGE
• What is the shell ?
• About this project
• Essentiel Fonctionalitie of the simple shell
• File description
• List of allowed functions and system calls fot this project
• Compilation
• valgrind
• Requierment
• Testing code
• Exemple
• BUGS
• Flowchart
• Authors

MAN_PAGE

What is the shell ?

A shell is a computer program that provides a user interface for the services of an operating system. It acts as a command interpreter, allowing the user to enter text commands to run programs, manipulate files, navigate directories, and interact with the operating system.

About this project

About this project simple shell is a simple version of the linux shell made by the holberton school.

Essential fonctionalities of the simple shell

Entry point of utilisateur Runs all "executable program" commands (ls, ls -l, /bin/ls, //bin/ls -l) Executes all buil_in commands (exit, env, getenv) manage commands with arguments manage the global PATH variable. manages the EOF condition (end of file) handles the Ctrl + c signal -> it does not leave the shell

Files description

• Shell.h -> header file
• simple_shell.c -> main function main: to enter command system and execute
• execve.c -> execute extern commands in the shell
• token.c -> strdup.c -> duplicate string and cut it in tokens
• free.c -> free the memory allocate for a 2D array
• read.c -> reads input line from the user and keep it in buffer
• path.c -> looks for the absolute path of an executable
• build.c -> used to handle build-in commands
• getenv.c -> get value of environment variable used to keep informations such as configuration parameters etc

List of allowed functions and system calls for this project

• all functions from string.h
• 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)
• printf (man 3 printf)
• fprintf (man 3 fprintf)
• vfprintf (man 3 vfprintf)
• sprintf (man 3 sprintf)
• putchar (man 3 putchar)
• 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)

Compilation

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

Testing valgrind

• root@9e07271f045e4bdfa379799071e5c5c9-2377118072:/holbertonschool-simple_shell# - -valgrind ./hsh
• ==165== Memcheck, a memory error detector
• ==165== Copyright (C) 2002-2017, and GNU GPL'd, by Julian Seward et al.
• ==165== Using Valgrind-3.18.1 and LibVEX; rerun with -h for copyright info
• ==165== Command: ./hsh
• ==165==
• $ valgrind ./hsh
• ==166== Memcheck, a memory error detector
• ==166== Copyright (C) 2002-2017, and GNU GPL'd, by Julian Seward et al.
• ==166== Using Valgrind-3.18.1 and LibVEX; rerun with -h for copyright info
• ==166== Command: ./hsh
• ==166==
• $ ^C==165==
• ==165== Process terminating with default action of signal 2 (SIGINT)
• ==166==
• ==166== Process terminating with default action of signal 2 (SIGINT)
• ==166== at 0x49747E2: read (read.c:26)
• ==165== at 0x494A3EA: wait4 (wait4.c:30)
• ==166== by 0x48ECC35: _IO_file_underflow@@GLIBC_2.2.5 (fileops.c:516)
• ==165== by 0x10961C: exec (in /holbertonschool-simple_shell/hsh)
• ==166== by 0x48E0307: getdelim (iogetdelim.c:73)
• ==165== by 0x109BC1: main (in /holbertonschool-simple_shell/hsh)
• ==166== by 0x109A9C: read_line (in /holbertonschool-simple_shell/hsh)
• ==166== by 0x109B21: main (in /holbertonschool-simple_shell/hsh)
• ==165==
• ==166==
• ==166== HEAP SUMMARY:
• ==166== in use at exit: 1,144 bytes in 2 blocks
• ==166== total heap usage: 2 allocs, 0 frees, 1,144 bytes allocated
• ==166==
• ==165== HEAP SUMMARY:
• ==165== in use at exit: 1,081 bytes in 5 blocks
• ==165== total heap usage: 26 allocs, 21 frees, 2,027 bytes allocated
• ==165==
• ==166== LEAK SUMMARY:
• ==166== definitely lost: 0 bytes in 0 blocks
• ==166== indirectly lost: 0 bytes in 0 blocks
• ==166== possibly lost: 0 bytes in 0 blocks
• ==166== still reachable: 1,144 bytes in 2 blocks
• ==166== suppressed: 0 bytes in 0 blocks
• ==166== Rerun with --leak-check=full to see details of leaked memory
• ==166==
• ==166== For lists of detected and suppressed errors, rerun with: -s
• ==166== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)
• ==165== LEAK SUMMARY:
• ==165== definitely lost: 0 bytes in 0 blocks
• ==165== indirectly lost: 0 bytes in 0 blocks
• ==165== possibly lost: 0 bytes in 0 blocks
• ==165== still reachable: 1,081 bytes in 5 blocks
• ==165== suppressed: 0 bytes in 0 blocks
• ==165== Rerun with --leak-check=full to see details of leaked memory
• ==165==
• ==165== For lists of detected and suppressed errors, rerun with: -s

Requierment

• General
• Allowed editors: vi, vim, emacs
• All your files will be compiled on Ubuntu 20.04 LTS using gcc, using the options -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
• Use system calls only when you need to (why?)

Testing code

• 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
• $

Exemple usage

• root@9e07271f045e4bdfa379799071e5c5c9-2377118072:/holbertonschool-simple_shell# gcc -Wall -Werror -Wextra -pedantic -std=gnu89 build.c exevce.c free.c getenv.c path.c read.c shell.h simple_shell.c strdup.c token.c -o hsh
• root@9e07271f045e4bdfa379799071e5c5c9-2377118072:/holbertonschool-simple_shell# ./hsh
• $ ls
• README.md build.c exevce.c free.c getenv.c hsh man_page.c path.c read.c shell.h simple_shell.c strdup.c token.c
• $ ls -l
• total 68
• -rw-r--r-- 1 root root 2190 Apr 23 13:32 README.md
• -rw-r--r-- 1 root root 1453 Apr 23 13:32 build.c
• -rw-r--r-- 1 root root 844 Apr 23 13:32 exevce.c
• -rw-r--r-- 1 root root 321 Apr 23 13:32 free.c
• -rw-r--r-- 1 root root 709 Apr 23 13:32 getenv.c
• -rwxr-xr-x 1 root root 17464 Apr 23 14:56 hsh
• -rw-r--r-- 1 root root 856 Apr 23 13:32 man_page.c
• -rw-r--r-- 1 root root 996 Apr 23 13:32 path.c
• -rw-r--r-- 1 root root 454 Apr 23 13:32 read.c
• -rw-r--r-- 1 root root 643 Apr 23 13:32 shell.h
• -rw-r--r-- 1 root root 700 Apr 23 13:32 simple_shell.c
• -rw-r--r-- 1 root root 283 Apr 23 13:32 strdup.c
• rw-r--r-- 1 root root 904 Apr 23 13:32 token.c
• $ /bin/ls
• README.md build.c exevce.c free.c getenv.c hsh man_page.c path.c read.c shell.h simple_shell.c strdup.c token.c
• $ /bin/ls -l
• total 68
• -rw-r--r-- 1 root root 2190 Apr 23 13:32 README.md
• -rw-r--r-- 1 root root 1453 Apr 23 13:32 build.c
• -rw-r--r-- 1 root root 844 Apr 23 13:32 exevce.c
• -rw-r--r-- 1 root root 321 Apr 23 13:32 free.c
• -rw-r--r-- 1 root root 709 Apr 23 13:32 getenv.c
• -rwxr-xr-x 1 root root 17464 Apr 23 14:56 hsh
• -rw-r--r-- 1 root root 856 Apr 23 13:32 man_page.c
• -rw-r--r-- 1 root root 996 Apr 23 13:32 path.c
• -rw-r--r-- 1 root root 454 Apr 23 13:32 read.c
• -rw-r--r-- 1 root root 643 Apr 23 13:32 shell.h
• -rw-r--r-- 1 root root 700 Apr 23 13:32 simple_shell.c
• -rw-r--r-- 1 root root 283 Apr 23 13:32 strdup.c
• -rw-r--r-- 1 root root 904 Apr 23 13:32 token.c

BUGS

No know Bugs

Flowchart