Example

     Using the dirname function, the following example reads a
     pathname, changes the current working directory to the parent
     directory, and opens a file.

           char path [MAXPATHLEN], *pathcopy;
           int fd;

           fgets(path, MAXPATHLEN, stdin);
           pathcopy = strdup(path);
           chdir(dirname(pathcopy));
           fd = open(basename(path), O_RDONLY);