Well, for C++:
[url]http://www.cplusplus.com/doc/tutorial/[/url]
[url]http://www.cs.wustl.edu/~schmidt/C++/[/url]
For *nix tutorials:
[url]http://www.comptechdoc.org/os/linux/howlinuxworks/[/url]
[url]http://www.comptechdoc.org/os/linux/howlinuxworks/linux_hlindex.html[/url]