Acronym for
Portable Operating System Interface for UNIX, a set of
IEEE and
ISO standards that define an interface between
programs and
operating systems. By designing their programs to conform to POSIX, developers have some assurance that their software can be easily
ported to POSIX-compliant operating systems. This includes most varieties of
UNIX.
The POSIX standards are now maintained by an arm of the IEEE called the Portable Applications Standards Committee (PASC).