cin and unknown number of integers

[superbonzo]

I`d still love to know what i can do in such a case, except for parsing the input char by char.

you can use getline and stringstream, or something like this to avoid excessive copying:

std::ifstream     file /* = ... */;
std::vector<int>  ints;

for( int val; file >> val; )
{
	ints.push_back( val );

	if( file.peek() == '\n' )
	{
		do_something_on( ints );
		ints.clear();
	}
}

but there are also boost iostream, boost serialization, regex's, etc ... etc ...