Gets the value of the _fileinfo variable, which determines what information about open files is passed to spawned processes.
Starting with Visual C++ 2005, _get_fileinfo is no longer supported in any Microsoft developer tools or libraries.
Returns zero if successful; an error code on failure. If pFileInfo is NULL, the invalid parameter handler is invoked, as described in Parameter Validation. If execution is allowed to continue, this function returns EINVAL and sets errno to EINVAL.