c++ boost split string

I'm using the boost::split method to split a string as this:

I first make sure to include the correct header to have access to boost::split:

#include <boost/algorithm/string.hpp>

then:

vector<string> strs;
boost::split(strs,line,boost::is_any_of("\t"));

and the line is like

"test   test2   test3"

This is how I consume the result string vector:

void printstrs(vector<string> strs)
{
    for(vector<string>::iterator it = strs.begin();it!=strs.end();++it)
    {
        cout << *it << "-------";
    }

    cout << endl;
}

But why in the result strs I only get "test2" and "test3", shouldn't be "test", "test2" and "test3", there are \t (tab) in the string.

Updated Apr 24th, 2011: It seemed after I changed one line of code at printstrs I can see the first string. I changed

cout << *it << "-------";

to

cout << *it << endl;

And it seemed "-------" covered the first string somehow.