什么是POSIX system

• 缘起

  《理解posixpath.py in Python》中提到，posixpath.py是针对POSIX系统的os.path源文件。

  From os.path, this is because different operating systems have different path name coventions.

• POSIX system

  From wikipedia, POSIX(Portable Operating System Interface) is a family of standards specifed by the IEEE Computer Society for maintaining compatibility between operating systems.

  POSIX( IEEE Std 1003.1-1988) defines the application programming interface (API), along with command line shells and utility interfaces, for software compatibility with variants of Unix and other operating systems.

  Unix was selected as the basic for a standard system interface partly because it was “manufacturer-neutral”

• Controversies

  POSIX mandates 512-byte default block sizes for the df and du utilities, reflecting the typical size of blocks on disks. When Richard Stallman and the GUN team were implementing POSIX for the GNU operating system, they objected to this on the grounds that most people think in terms of 1024 byte(1 KiB) blocks.

• POSIX-oriented operating systems

  Depending upon the degree of compliance with the standards, on can classify operating systems as fully or partly POSIX compatible. Certified products can be found at the IEEE’s website.

  • POSIX-certified

    macOS, Solaris

  • Mostly POSIX-compliant

    Android, OpenBSD, Linux, SkyOS, VMware ESXi

  • POSIX for Microsoft Windows

    WSL

• References

1. What is the meaning of “POSIX”?
2. What is POSIX? Richard Stallman explains