According to the theme in the online version ,
POSIX.1-2008 is both the IEEE Std 1003.1 ™ -2008 standard and the basic specifications of the Open Group core technical standard, Issue 7. In this 2013 release, IEEE Std 1003.1-2008 / Cor 1-2013 is included in IEEE Std 1003.1-2008 (base document). The 2013 edition includes Technical Corrigendum 1 regarding issues discovered since the approval of the 2008 edition.
Technical Corrigendum 1, containing the change as a large, unorganized “patch,” is freely available from IEC. It seems that most, if not all changes, can also be viewed in your error tracker, requesting attached errors in the tc1-2008 tag. A quick glance reveals minor clarifications and changes that span everything from regular expressions to the file system to setjmp .