POSIX (Portable Operating System Interface) is a specification for a Unix operating system promulgated by the IEEE. The intent is to provide some uniformity, consistency, and code portability between operating systems when performing standard tasks. Fully POSIX compliant Unixes exist. In addition, many operating systems include POSIX compatible features. POSIX features are present in some non-Unix OSes including Windows NT.

POSIX was first proposed in 1986. The standard is controlled and administered by an organization called the PACS. Draft standards proposed by the PACS working groups are approved by the IEEE

There are several major issues with POSIX. One is the handling of pre-existing non-POSIX compliant interfaces in existing software. Are they to continue to be supported? A second is the provision of new features that clearly require user experience before freezing their user interface into a standard.

Return To Index Copyright 1994-2008 by Donald Kenney.