Most of the functions in TOOLHELP.DLL use structures to return information. The first member in each of these structures is a doubleword value named dwSize. This value must be initialized before an application calls the function that uses the structure; otherwise, the function fails.
The dwSize member enables new versions of TOOLHELP.DLL to include additional features without breaking code written for structures in Windows versions earlier than 3.1.
The THSAMPLE.C sample program demonstrates how to use some of the functions in TOOLHELP.DLL. For a full description of these functions, see the Microsoft Windows Programmer's Reference, Volume 2. For a full description of the TOOLHELP.DLL structures, see the Microsoft Windows Programmer's Reference, Volume 3.