I will check it on monday, but if i good remember SPACE=(TRK,(15,0)) let you allocate dataset with exacly 15 tracks.
Referring to your space parameter,i do not know what kind of dataset you write about, but the second paramerer describes size of the extents. Number of extents depends of type of dataset.
When we r creating a data set(PS) using 3.2 option, I just want to show the default values for primary n secondary space as 15,15 tracks. Also when the user tries o give more than the default values, i should not allow. This is what i need to do..