The Microsoft run-time library provides the following global variables. These global variables have been deprecated in Visual C++ 2005 for the more secure functional versions, which should be used in place of the global variable (except _pgmptr and _wpgmptr).
Controls memory heap granularity
Adjust for local time; used in some date and time functions
Store error codes and related information
Pointers to arrays of pointers to strings that constitute process environment
Specifies whether information regarding open files of a process is passed to new processes
Sets default file-translation mode
Contain information used by the character classification functions.
Initialized at program startup to value such as program name, filename, relative path, or full path