i386_set_ldt differences between 4.x and 5.x?

[Tijl Coosemans]

i386_set_ldt(int start_sel, union descriptor *descs, int num_sels);

The man page for this function in FreeBSD 5.x mentions the following:

"If num_descs is 1, start_sels is valid, and descs is NULL, then 
i386_set_ldt() will free that descriptor (making it available to be 
reallocated again later)."

Am I right when I say this is only because 5.x allows dynamic allocation 
of descriptors and that freeing a descriptor isn't necessary for 
pre-5.0 versions of FreeBSD (and current versions of Net/OpenBSD)?