int QSget_row_index (QSprob p, const char *name, int *rowindex)
/* p is an initialized QSprob, a handle to an existing LP problem  */
/* Find the index of the constraint r1.                            */

int rval, rowindex;
const char *name = "r1";

rval = QSget_row_index (p, name, &rowindex);
if (rval) {
    fprintf (stderr, "could not get index, error code %d\n", rval);
} else {
    if (rowindex == -1) {
        printf ("%s is not in the problem\n", name);
    } else {
        printf ("%s is row number %d\n", name, rowindex);
    }
}