TCHAR *useful_environment(TCHAR *);
TCHAR *expand_environment_string(TCHAR *);
int set_environment_block(TCHAR *);
int clear_environment();
int duplicate_environment(TCHAR *);
int test_environment(TCHAR *);
TCHAR *useful_environment(TCHAR *);
TCHAR *expand_environment_string(TCHAR *);
int set_environment_block(TCHAR *);
int clear_environment();
int duplicate_environment(TCHAR *);
int test_environment(TCHAR *);