Mini Shell

This shell mirrors the functionalities of a standard bash shell. Here are its key features:

• Displays a prompt upon completion of a foreground process.
• Supports ; and & to separate commands. Treats ; as a new-line character and & as an indicator for a background process.
• Allows the usage of pipes and redirection arrows.
• Performs commands similar to terminal actions:
  • warp: akin to cd
  • peek: akin to ls, supporting the same flags and input format.
• Past Events: Tracks up to 15 past commands. Functions (usage):
  • pastevents: Displays past commands in order of recent use.
  • pastevents purge: Clears all past command information.
  • pastevents execute <num>: Executes the <num>-th last command.
• Proclore Function: Displays the following information on a process: PID, Process status, Process Group, Virtual memory, Executable path.
• Seek Function: Searches for a file/directory in a specified or current directory and returns relative paths of matching files/directories. Flags:
  • -d: Look for directories (ignore files even if the name matches).
  • -f: Look for files (ignore directories even if the name matches).
  • -e: Execute/change directory based on a single match.
    • This flag is effective only when a single file or a single directory with the name is found.
    • If only one file (and no directories) is found, then prints its output.
    • If only one directory (and no files) is found, then changes the current working directory to it.
    • Otherwise, the flag has no effect.
    • Works in conjunction with -d and -f flags.
    • If -e flag is enabled but the directory lacks access permission (execute) or the file lacks read permission, it outputs "Missing permissions for the task!".
• Activities Function: Lists processes spawned by the shell in lexicographic order. Information includes Command Name, PID, and state (running or stopped).
• Neonate Function: Prints the PID of the most recently created process. Continuously prints every [time_arg] seconds until the 'x' key is pressed. Usage: neonate or neonate -n <time_arg>.
• iMan Command: Fetches the man page of a specified command. Usage: iMan <command_name>.

Concepts and Ideas Utilized

• fork, wait
• System calls
• Networking with TCP
• Raw and cooked mode
• Knowledge of Linux

Note: Ensure proper permissions for execution and file access to avoid errors.