Thomas Faber thfabba@gmx.de writes:
/* no buffer, determine length */
SetLastError(0xdeadbeef);
ret = pGetDllDirectoryA(0, NULL);
error = GetLastError();
ok(ret == length + 1, "Expected %u, got %u\n", length + 1, ret);
ok(error == 0xdeadbeef, "Error is %u\n", error);
Testing last error on success is generally not useful.