The TBM_GETTICPOS message retrieves the current physical position of a tick mark in a trackbar.
TBM_GETTICPOS
wParam = (WPARAM) (WORD) iTic;
lParam = 0;
Parameters
iTic
Zero-based index identifying a tick mark.
Return Values
Returns the physical position, in client coordinates, of the specified tick mark or - 1 if iTic does not specify a valid index.