如何通过提供文件名获得完整路径?

请帮助我没有得到如何使用C / C ++实现返回该文件的完整路径的函数?

UNIX / Linux的:

#include  #include  char *full_path = realpath("foo.dat", NULL); ... free(full_path); 

要么:

 char full_path[PATH_MAX]; realpath("foo.dat", full_path); 

视窗:

 #include  TCHAR full_path[MAX_PATH]; GetFullPathName(_T("foo.dat"), MAX_PATH, full_path, NULL);