filename_symlinkat
return filename_symlinkat(old, AT_FDCWD, new);
int filename_symlinkat(struct filename *from, int newdfd, struct filename *to);
return filename_symlinkat(old, newdfd, new);
return filename_symlinkat(old, AT_FDCWD, new);
ret = filename_symlinkat(old, sl->new_dfd, new);