Revision Standard - Inactive-Withdrawn. This 2004 Edition includes IEEE Std 1003.1-2001/Cor 1-2002 and IEEE Std 1003.1-2001/Cor 2-2004 incorporated into IEEE Std 1003.1-2001 (the base document). The two Corrigenda address problems discovered since the approval of IEEE Std 1003.1-2001. These changes are mainly due to resolving integration issues raised by the merger of the base documents that were incorporated into IEEE Std 1003.1-2001, which is the single common revision to IEEE Std 1003.1TM-1996, IEEE Std 1003.2TM-1992, ISO/IEC 9945-1: 1996, ISO/IEC 9945-2: 1993, and the Base Specifications of The Open Group Single UNIX¿¿ Specification, Version 2. This standard defines a standard operating system interface and environment, including a command interpreter (or "shell"), and common utility programs to support applications portability at the source code level. This standard is intended to be used by both applications developers and system implementors and comprises four major components (each in an associated volume)