Childprocess

Childprocess is a term used in computing to describe a process created by another process, known as the parent. The child runs independently but is often coordinated with its parent, sharing resources such as environment variables and standard input/output streams. A child process has its own process identifier and may execute concurrently with its parent, enabling parallel work and task isolation.

Creation and management: In Unix-like systems, a parent creates a child by forking the current process and then replacing it with a program image using an exec call. In Windows, new processes are created with APIs such as CreateProcess. Many programming languages provide higher-level abstractions to spawn child processes without exposing low-level details, simplifying cross-platform use.

Communication and lifecycle: Parent and child can communicate via pipes or sockets; standard input, output, and error streams are commonly used. The parent can wait for the child to exit, retrieve its exit code, or terminate it if needed. Proper handling helps avoid zombie processes and ensures resources are released. Signals or termination requests can be used to control child behavior, with platform-specific differences in handling.

Node.js example: The Node.js runtime includes a module that exposes APIs to spawn and manage child processes. Methods such as spawn, exec, and execFile create child processes with configurable I/O behavior. A specialized function is often available to fork a new Node.js process and enable inter-process communication through message passing.

Security and best practices: When invoking external programs, it is important to avoid shell interpretation when possible to prevent injection attacks. Use explicit argument lists, validate inputs, and prefer dedicated APIs for inter-process communication. Always handle errors and ensure timely cleanup of child processes to prevent resource leaks or orphan processes.