INT 20 - Program Terminate

CS = address of ~PSP~

returns nothing

- INT 20 restores the terminate, ~Ctrl-Break~, and critical error

exit addresses from values in the PSP, flushes all buffers, frees

memory and returns to DOS via the termination handler address

- does not close ~FCB~s

- this function is no longer recommended, but can be used by

version of DOS before 2.0, see ~INT 21,4C~ and ~INT 21,0~