Write Code That Works on the Largest Number of Platforms
You can port your Visual C++ applications to UNIX using the Standard C++ libraries and the Visual C++ compiler libraries. Many UNIX functions, such as open, fopen, read, and write, are available in the Visual C++ run-time library. Also, there is a one-to-one mapping of these UNIX APIs to Win32 APIs: open to CreateFile, read to ReadFile, write to WriteFile, ioctl to DeviceIOControl, close to CloseFile, and so on. Many of the traditional system calls relied on by UNIX applications are available as Win32 APIs. See Port from UNIX to Win32 for a discussion of compatibility issues, such as multithreading.
You need to consider UNIX when writing your C/C++ code; for example, UNIX file names are case-sensitive. See UNIX for compatibility guidelines when porting Visual C++ to UNIX.