output to a file

i would like my TI MSP430F169 to read data from a source, say a magnetic field, and then record this to the SD card on the CubeSat kit.
i've searched high and low and can't find any way to do this with Rowleys CrossWorks 1.3. Maybe i'm looking in the wrong places but a nudge in the right direction would do marvelously.
¬ is it something to do with _fprintf()?
in normal C i would just do the following:
code:
#include <iostream.h>
#include <fstream.h>
#include <threevector.h>
using namespace std;...
int main(void)
{
ofstream outfile(results.txt);
threevector v0;
outfile << "some text";
v0.print(outfile);...
}
clearly this doesnt work with crossworks.
i'd like to first print to a file and then try it out with the SD card if at all the procedure is different?
many thanx!