0x15. C - Simple Shell

Description

This team project is part of the first year curriculum of ALX Software Engineering Program. Simple Shell is a command line interpreter that replicates the sh program on Linux. It can take in simple commands to navigate the terminal, manipulate files, and execute programs.

What we learned:

How a shell works and finds commands
Creating, forking and working with processes
Executing a program from another program
Handling dynamic memory allocation in a large program
Pair programming and team work
Building a test suite to check our own code

Compile and run

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

./hsh

Usage

Prints a prompt and waits for a command from the user
Creates a child process in which the command is checked
Checks for built-ins, aliases in the PATH, and local executable programs
The child process is replaced by the command, which accepts arguments
When the command is done, the program returns to the parent process and prints the prompt
The program is ready to receive a new command
To exit: press Ctrl-D or enter "exit" (with or without a status)
Works also in non interactive mode

Examples

$ /bin/ls
foo main.c coquille.c README.md tests croissant.c

$ pwd
/home/vagrant/simple_shell

$ ls -l
total 60
drwxrwxr-x 7 vagrant vagrant  4096 Apr  7 01:48 foo
-rw-rw-r-- 1 vagrant vagrant   148 Apr  7 00:00 main.c
-rwxrw-r-- 1 vagrant vagrant    28 Apr  7 15:35 coquille.c

$ baguette
./hsh: No such file or directory

$ echo "cat testfile" | ./hsh
This is a test file

Files

File	Content
main.c	entry point, executing function
shell.h	function prototypes, standard libraries, structs
print_funcs.c	printing functions
print_errors.c	error printing functions
string_funcs_1.c	string-handling functions
string_funcs_2.c	string-handling functions
list_funcs_1.c	linked list handling functions
list_funcs_2.c	linked list handling functions
tokenize.c	string to tokens parsing functions
path_finder.c	functions that check the PATH for commands
builtins.c	functions dealing with the shell builtins
set_env.c	functions dealing with the setenv/unsetenv builtins
helper_funcs.c	memory and signal handling functions
convert_funcs.c	conversion between string and number functions
man_1_simple_shell	Simple Shell man page (`man ./man_1_simple_shell`)

Authors

Olatunji Sobayo

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Aspiring Full-Stack Software Engineer

Golden Dennar Tanimowo