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1. Process Creation and Management

Fork System Call (fork_example.c)

• fork() creates a new child process that runs concurrently with the parent.
• The child receives a process ID (PID) and inherits the parent’s memory.
• getpid() and getppid() functions return process ID and parent process ID.
• wait() ensures that the parent waits for the child to complete before continuing.
• A file is used for logging process execution.

OS Concept: Process Creation, Parent-Child Relationship, Synchronization

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2. Inter-Process Communication (IPC)

Pipelines (pipelines_example.c)

• A pipeline (pipe()) establishes a unidirectional communication channel between processes.
• Uses Parent-to-Child and Child-to-Parent pipes.
• write() and read() are used for data transfer.
• Round-Robin & Random Scheduling: Parent assigns jobs to child processes using different strategies.

OS Concept: IPC Mechanisms, Pipes, Scheduling, Process Synchronization

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Sockets (sockets_example.c)

• Client-Server Communication using Sockets
• socket() creates a communication endpoint.
• connect() links the client to a remote server.
• Polling (poll()) monitors multiple file descriptors for events.
• Uses TCP (SOCK_STREAM) for reliable communication.
• Non-blocking I/O: poll() ensures responsiveness.

OS Concept: Network Communication, Client-Server Model, Polling, Non-Blocking I/O

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3. Process Synchronization & Signals

Gates System (gates_parent.c & gates_child.c)

• The Parent Process creates child processes (gates) that toggle states based on signals.
• Signals Used:
  • SIGUSR1: Reports gate status.
  • SIGUSR2: Toggles gate state.
  • SIGALRM: Timer-based automatic status updates.
  • SIGCHLD: Used by the parent to detect child process termination.
  • SIGTERM: Graceful termination.

OS Concept: Signal Handling, Process Synchronization, Event Handling

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4. Process Scheduling & Handling

• Round-Robin and Random Job Assignment (pipelines_example.c) demonstrate different scheduling policies.
• Process Replacement (execv()) in gates management ensures continuity after a child exits.
• Process Termination (kill()) in multiple files (gates_parent.c, pipelines_example.c) controls the lifetime of child processes.

OS Concept: Scheduling, Process Replacement, Process Termination, Resource Management

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These concepts are essential in OS Design, covering process control, IPC, networking, and synchronization.