Make it :

make
./minishell

Introduction :

• The existence of shells is linked to the very existence of IT
• At the time, all developers agreed that communicating with a computer using aligned 1/0 switches was seriously irritating.
• It was only logical that they came up with the idea of creating a software to communicate with a computer using interactive lines of commands in a language somewhat close to the human language.
• Thanks to Minishell, you’ll be able to travel through time and come back to problems people faced when Windows didn’t exist.

Rules

We display a prompt when waiting for a new command.

All the features we implemented :

• Have a working history.

• Search and launch the right executable (based on the PATH variable or using a relative or an absolute path).

• Not use more than one global variable. Think about it. You will have to explain its purpose.

• Not interpret unclosed quotes or special characters which are not required by the subject such as \ (backslash) or ; (semicolon).

• Handle ’ (single quote) which should prevent the shell from interpreting the metacharacters in the quoted sequence.

• Handle " (double quote) which should prevent the shell from interpreting the metacharacters in the quoted sequence except for $ (dollar sign).

• Implement redirections:

  • '<' should redirect input.
  • '>' should redirect output.
  • '<<' should be given a delimiter, then read the input until a line containing the delimiter is seen. However, it doesn’t have to update the history!
  • '>>' should redirect output in append mode.

• Implement pipes (| character). The output of each command in the pipeline is connected to the input of the next command via a pipe.

• Handle environment variables ($ followed by a sequence of characters) which should expand to their values.

• Handle $? which should expand to the exit status of the most recently executed foreground pipeline.

• Handle ctrl-C, ctrl-D and ctrl-\ which should behave like in bash.

• In interactive mode:

  • ctrl-C displays a new prompt on a new line.
  • ctrl-D exits the shell.
  • ctrl-\ does nothing.

• Your shell must implement the following builtins:

  • echo with option -n
  • cd with only a relative or absolute path
  • pwd with no options
  • export with no options
  • unset with no options
  • env with no options or arguments
  • exit with no options

The readline() function can cause memory leaks.