Simple Shell

This is a simple UNIX interpreter written in C.

Usage

All the files are compiled on an Ubuntu 20.04 LTS machine with:

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

Once compiled to start the program , run: ./hsh

To exit the shell run: $ exit

The shell supports most shell commands, such as cat, pwd, ls and lots more.

Testing

The shell works as the following 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.cshell.c test_ls_2
$

Built-ins

The following built-ins are supported by the hsh shell:

• env - Prints the current environment.
• setenv VARIABLE VALUE - Initializes a new environment VARIABLE with VALUE, or modifies an existing VARIABLE with VALUE.
• unsetenv VARIABLE- Removes an environment variable.

Return Value

Hsh shell will exit with status 0 unless status is specified with syntax exit VALUE.

Authors

• Daniel Musau
• Carol Waithaka