20 Oct 2018

POSIX

POSIX - Portable Operating System Interface

→ A family of standards specified by IEEE for maintaining compatibility among operating systems

→ Any software that conforms to POSIX standards should be compatible with other operating systems that adhere to POSIX

There are currently more than 20 standards under the POSIX umbrella.

POSIX standards define:

  1. System Calls: tasks like file I/O, process management, memory management, and inter-process communication.
  2. Utilities: command-line utilities and tools, like ls, cp, and grep, along with their command-line options and behavior.
  3. File System Hierarchy: POSIX defines a standard file system hierarchy, including directories like /bin, /usr, and /lib.
  4. Environment Variables: POSIX specifies standard environment variables, which help programs locate essential system resources and configuration data.
  5. Shell Command Language: POSIX defines a standardized shell command language and scripting syntax, which is the basis for Unix shells like bash.