Re: Promoting unsigned long int to long int

btw can i sort an array of pointers with qsort function ?? I tried the
following but failed miserably as it reutrned the same unsorted list :


int cmp_coord_x(const void *vpa, const void *vpb)
{
const vector *va = vpa;
const vector *vb = vpb;

return (va->coord[0] < va->coord[0] ? -1 : vb->coord[0] > vb-
coord[0]);
}

int cmp_coord_y(const void *vpa, const void *vpb)
{
const vector *va = vpa;
const vector *vb = vpb;

return (va->coord[1] < va->coord[1] ? -1 : vb->coord[1] > vb-
coord[1]);
}

int cmp_coord_z(const void *vpa, const void *vpb)
{
const vector *va = vpa;
const vector *vb = vpb;

return (va->coord[2] < va->coord[2] ? -1 : vb->coord[2] > vb-
coord[2]);
}

/* axis is used as criterion on how we sort the array */
if (axis == 0)
{
qsort(parent_vpa, sizeof parent_vpa/ sizeof *parent_vpa,
sizeof *parent_vpa, cmp_coord_x);
}
if (axis == 1)
{
qsort(parent_vpa, sizeof parent_vpa/ sizeof *parent_vpa,
sizeof *parent_vpa, cmp_coord_y);
}
if (axis == 2)
{
qsort(parent_vpa, sizeof parent_vpa/ sizeof *parent_vpa,
sizeof *parent_vpa, cmp_coord_z);
}
.