In order to ensure consistency between operating systems, IEEE formalized some standards for operating systems. These are described in the following sections.
Understanding the POSIX standard
POSIX standards and features
Portable Operating System Interface (POSIX) for Unix represents a series of standards for operating system interfaces. The first version dates back to 1988 and covers a series of topics like filenames, shells, and regular expressions.
There are many features defined by POSIX, and they are organized in four different standards, each one focusing on a different aspect of the Unix compliance. They are all named POSIX followed by a number.
