Minishell

Compile

make

Mandatory

• Display a prompt when waiting for a new command.
• Have a working history.
• Search and launch the right executable (based on the PATH variable or using a relative or an absolute path).
• Avoid using more than one global variable to indicate a received signal. Consider the implications: this approach ensures that your signal handler will not access your main data structures.
• 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

Bonus

• && and || with parenthesis for priorities.
• Wildcards * should work for the current working directory.