OS/2 functions that used to take a PSZ as a parameter, and that do not modify the contents of the passed string, have been updated in the C++ header files to take a PCSZ data type parameter. The use of PCSZ allows for better optimization by the compiler and is more semantically compatible with C++. Existing code that calls functions that use PSZ will continue to work correctly.

Several of the typedefs have been changed in the C++ header files. For example, many items that are unsigned char in the C header files are char in the C++ header files. For instance,

typedef unsigned char BYTE;

typedef char BYTE;

The existing samples that are included in the IBM Developer's Toolkit for OS/2 Warp Version 3 can be used with either set of the header files.