External environment refers to the major factors and forces outside the organization that have the potential to significantly affect the performance of an organization. External environment is divided into two parts i.e. mega environment or general environment and specific or task environment.
_tcscat is a C function, to concatenate C-style strings; CString is a class (which has built in concatenation via operator+), not a C-style string.
For more detailed information about multithreaded applications, see the documentation of your threads functions. Pro*C/C++ supports development of multithreaded Oracle Server applications (on platforms that support multithreaded applications) using the following: A command-line option to generate thread-safe code.