how do I temporarily stop ginput for right button (button ==3)?

I want to place a 'flag' in a matrix, when the right button (button == 3) has been placed. However, when I try to enable ginput for that specific cell, I just turn of ginput for the entire matrix... How can I make this happen for only that cell? I have tried many things already, but this is the final product I am struggeling with at the moment.... any tips?

 elseif button == 3 % right click
 text(x-0.9,y-0.5,'Flag')
 flag_matrix(a,b)= bombboard_to_matrix(x,y);
 flag_matrix(a,b)=10;
 if flag_matrix(a,b)== 10;
 [a,b,button]=ginput(1);
 ginput off;
 end;