C++ Write to file but no overwrite

[LittleQuick]

I've already read " http://www.cplusplus.com/doc/tutorial/files/ ", maybe I didn't look close enough. But is there a way to keep writing to files, like a log, but never writing over the past entry? I am stumped, please help.
rough example [() - C++, "" - txt file output] (cin >> log;) "log1", (cin >> log2) "log1, log2". (Something like that, I am in a rush sorry.)

[Albatross]

There is indeed! Read the parameters section here:
http://cplusplus.com/reference/iostream/ofstream/open/

-Albatross

[LittleQuick]

Ah! I see! As always Albatross to the rescue. Thank you so much!!