Skip to content

Command_Line_Client.md

Latest commit

 

History

History
90 lines (54 loc) · 3.06 KB

Command_Line_Client.md

File metadata and controls

90 lines (54 loc) · 3.06 KB
graph LR
    Main_Loop_REPL_["Main Loop (REPL)"]
    Command_Parser["Command Parser"]
    Execution_Engine["Execution Engine"]
    Job_Manager["Job Manager"]
    Built_in_Command_Handler["Built-in Command Handler"]
    Signal_Handler["Signal Handler"]
    Main_Loop_REPL_ -- "passes command to" --> Command_Parser
    Command_Parser -- "invokes" --> Built_in_Command_Handler
    Command_Parser -- "passes command to" --> Execution_Engine
    Execution_Engine -- "adds job to" --> Job_Manager
    Execution_Engine -- "waits for job in" --> Job_Manager
    Built_in_Command_Handler -- "modifies job state in" --> Job_Manager
    Built_in_Command_Handler -- "reads job list from" --> Job_Manager
    Signal_Handler -- "removes job from" --> Job_Manager
    Signal_Handler -- "updates job status in" --> Job_Manager
Loading

CodeBoardingDemoContact

Details

One paragraph explaining the functionality which is represented by this graph. What the main flow is and what is its purpose.

Main Loop (REPL)

The heart of the shell. It repeatedly prints a prompt, reads a line of user input, and orchestrates the command evaluation process.

Related Classes/Methods:

  • eval (1:1)

Command Parser

Responsible for parsing the raw command line string into a structured format. It identifies the command, its arguments, and determines if it's a built-in command or an external program.

Related Classes/Methods:

  • parseline (1:1)

Execution Engine

Executes external commands. It handles forking a new process and using execve to replace the child process's image with the new program. It manages waiting for foreground jobs to complete.

Related Classes/Methods:

  • fork (1:1)
  • execve (1:1)

Job Manager

Maintains a list of all running background and foreground jobs. It is responsible for adding, deleting, and retrieving jobs from this list. This component is critical for features like jobs, bg, and fg.

Related Classes/Methods:

  • addjob (1:1)
  • deletejob (1:1)
  • getjob (1:1)

Built-in Command Handler

Implements the shell's internal commands, such as quit, jobs, bg, and fg. It directly manipulates the shell's state, such as the job list, without creating new processes.

Related Classes/Methods:

  • quit (1:1)
  • jobs (1:1)
  • bg (1:1)
  • fg (1:1)

Signal Handler

Manages asynchronous system signals. It is responsible for catching signals like SIGINT (Ctrl-C), SIGTSTP (Ctrl-Z), and SIGCHLD (when a child process terminates or stops) to manage job state correctly.

Related Classes/Methods:

  • SIGINT (1:1)
  • SIGTSTP (1:1)
  • SIGCHLD (1:1)

FAQ